diff --git a/fortran/lammps.f90 b/fortran/lammps.f90
index fc318091bf..18b8fa89a3 100644
--- a/fortran/lammps.f90
+++ b/fortran/lammps.f90
@@ -2682,8 +2682,8 @@ CONTAINS
     CHARACTER(LEN=*), INTENT(IN) :: id
     REAL(c_double), DIMENSION(:,:), TARGET, INTENT(IN) :: virial
     TYPE(c_ptr) :: Cid, Cvirial
-    TYPE(c_ptr), TARGET :: Cptr
-    INTEGER(c_int) :: nlocal
+    TYPE(c_ptr), DIMENSION(:), ALLOCATABLE, TARGET :: Cptr
+    INTEGER(c_int) :: nlocal, i
 
     nlocal = lmp_extract_setting(self, 'nlocal')
     IF (SIZE(virial,2) < nlocal .OR. SIZE(virial,1) /= 6) THEN
@@ -2692,10 +2692,14 @@ CONTAINS
         &[Fortran/fix_external_set_energy_peratom]')
     END IF
     Cid = f2c_string(id)
-    Cptr = C_LOC(virial(1,1))
-    Cvirial = C_LOC(Cptr)
+    ALLOCATE(Cptr(nlocal))
+    DO i = 1, nlocal
+      Cptr(i) = C_LOC(virial(1,i))
+    END DO
+    Cvirial = C_LOC(Cptr(1))
     CALL lammps_fix_external_set_virial_peratom(self%handle, Cid, Cvirial)
     CALL lammps_free(Cid)
+    DEALLOCATE(Cptr)
   END SUBROUTINE lmp_fix_external_set_virial_peratom
 
   SUBROUTINE lmp_fix_external_set_vector_length(self, id, length)
diff --git a/unittest/fortran/test_fortran_fixexternal.f90 b/unittest/fortran/test_fortran_fixexternal.f90
index ca08e3c4d9..61fea1be9d 100644
--- a/unittest/fortran/test_fortran_fixexternal.f90
+++ b/unittest/fortran/test_fortran_fixexternal.f90
@@ -4,6 +4,7 @@ MODULE ext_stuff
   USE LIBLAMMPS
   IMPLICIT NONE
 
+  INTEGER, PARAMETER :: vec_length = 8
   REAL(c_double), SAVE :: direction = 1.0_c_double
   REAL(c_double), DIMENSION(:,:), POINTER, SAVE :: f3 => NULL(), f4 => NULL()
 
@@ -20,21 +21,35 @@ CONTAINS
     REAL(c_double), DIMENSION(:,:), INTENT(IN) :: x
     REAL(c_double), DIMENSION(:,:), INTENT(OUT) :: f
     REAL(c_double), DIMENSION(SIZE(id)) :: e
+    REAL(c_double), DIMENSION(6,SIZE(id)) :: v
 
     WHERE (id == 1)
       f(1,:) = 1.0_c_double
       f(2,:) = -1.0_c_double
       f(3,:) = 1.25_c_double
       e = 1.0_c_double
+      v(1,:) = 1.0_c_double
+      v(2,:) = 2.0_c_double
+      v(3,:) = -1.0_c_double
+      v(4,:) = -2.0_c_double
+      v(5,:) = 3.0_c_double
+      v(6,:) = -3.0_c_double
     ELSEWHERE
       f(1,:) = -1.0_c_double
       f(2,:) = +1.0_c_double
       f(3,:) = -1.25_c_double
       e = 10.0_c_double
+      v(1,:) = 10.0_c_double
+      v(2,:) = 20.0_c_double
+      v(3,:) = -10.0_c_double
+      v(4,:) = -20.0_c_double
+      v(5,:) = 30.0_c_double
+      v(6,:) = -30.0_c_double
     END WHERE
     SELECT TYPE (instance)
       CLASS IS (lammps)
         CALL instance%fix_external_set_energy_peratom('ext1', e)
+        CALL instance%fix_external_set_virial_peratom('ext1', v)
       CLASS DEFAULT
         WRITE(0,*) 'UMM...this should never happen.'
         STOP 1
@@ -48,21 +63,35 @@ CONTAINS
     REAL(c_double), DIMENSION(:,:), INTENT(IN) :: x
     REAL(c_double), DIMENSION(:,:), INTENT(OUT) :: f
     REAL(c_double), DIMENSION(SIZE(id)) :: e
+    REAL(c_double), DIMENSION(6,SIZE(id)) :: v
 
     WHERE (id == 1_c_int)
       f(1,:) = 1.0_c_double
       f(2,:) = -1.0_c_double
       f(3,:) = 1.25_c_double
       e = 1.0_c_double
+      v(1,:) = 1.0_c_double
+      v(2,:) = 2.0_c_double
+      v(3,:) = -1.0_c_double
+      v(4,:) = -2.0_c_double
+      v(5,:) = 3.0_c_double
+      v(6,:) = -3.0_c_double
     ELSEWHERE
       f(1,:) = -1.0_c_double
       f(2,:) = +1.0_c_double
       f(3,:) = -1.25_c_double
       e = 10.0_c_double
+      v(1,:) = 10.0_c_double
+      v(2,:) = 20.0_c_double
+      v(3,:) = -10.0_c_double
+      v(4,:) = -20.0_c_double
+      v(5,:) = 30.0_c_double
+      v(6,:) = -30.0_c_double
     END WHERE
     SELECT TYPE (instance)
       CLASS IS (lammps)
         CALL instance%fix_external_set_energy_peratom('ext1', e)
+        CALL instance%fix_external_set_virial_peratom('ext1', v)
       CLASS DEFAULT
         WRITE(0,*) 'UMM...this should never happen.'
         STOP 1
@@ -76,21 +105,35 @@ CONTAINS
     REAL(c_double), DIMENSION(:,:), INTENT(IN) :: x
     REAL(c_double), DIMENSION(:,:), INTENT(OUT) :: f
     REAL(c_double), DIMENSION(SIZE(id)) :: e
+    REAL(c_double), DIMENSION(6,SIZE(id)) :: v
 
     WHERE (id == 1_c_int64_t)
       f(1,:) = 1.0_c_double
       f(2,:) = -1.0_c_double
       f(3,:) = 1.25_c_double
       e = 1.0_c_double
+      v(1,:) = 1.0_c_double
+      v(2,:) = 2.0_c_double
+      v(3,:) = -1.0_c_double
+      v(4,:) = -2.0_c_double
+      v(5,:) = 3.0_c_double
+      v(6,:) = -3.0_c_double
     ELSEWHERE
       f(1,:) = -1.0_c_double
       f(2,:) = +1.0_c_double
       f(3,:) = -1.25_c_double
       e = 10.0_c_double
+      v(1,:) = 10.0_c_double
+      v(2,:) = 20.0_c_double
+      v(3,:) = -10.0_c_double
+      v(4,:) = -20.0_c_double
+      v(5,:) = 30.0_c_double
+      v(6,:) = -30.0_c_double
     END WHERE
     SELECT TYPE (instance)
       CLASS IS (lammps)
         CALL instance%fix_external_set_energy_peratom('ext1', e)
+        CALL instance%fix_external_set_virial_peratom('ext1', v)
       CLASS DEFAULT
         WRITE(0,*) 'UMM...this should never happen.'
         STOP 1
@@ -201,6 +244,7 @@ END SUBROUTINE f_lammps_close
 SUBROUTINE f_lammps_setup_fix_external_callback() BIND(C)
   USE LIBLAMMPS
   USE keepstuff, ONLY : lmp, demo_input, cont_input, pair_input
+  USE ext_stuff, ONLY : vec_length
   IMPLICIT NONE
 
   CALL lmp%commands_list(demo_input)
@@ -209,6 +253,7 @@ SUBROUTINE f_lammps_setup_fix_external_callback() BIND(C)
   CALL lmp%command('neigh_modify exclude group all all')
   CALL lmp%command('fix ext1 all external pf/callback 1 1')
   CALL lmp%command('fix ext2 all external pf/callback 1 1')
+  CALL lmp%fix_external_set_vector_length('ext2', vec_length)
 END SUBROUTINE f_lammps_setup_fix_external_callback
 
 SUBROUTINE f_lammps_setup_fix_external_array() BIND(C)
@@ -305,6 +350,9 @@ SUBROUTINE f_lammps_find_forces() BIND(C)
       f3(1,:) = 4.0_c_double
       f3(2,:) = -4.0_c_double
       f3(3,:) = 6.0_c_double
+      f4(1,:) = 10.0_c_double
+      f4(2,:) = -10.0_c_double
+      f4(3,:) = 12.0_c_double
     ELSEWHERE
       f3(1,:) = 5.0_c_double
       f3(2,:) = -5.0_c_double
@@ -334,3 +382,43 @@ SUBROUTINE f_lammps_set_virial() BIND(C)
   CALL lmp%fix_external_set_virial_global('ext4', [1.0_c_double, &
     2.0_c_double, 2.5_c_double, -1.0_c_double, -2.25_c_double, -3.02_c_double])
 END SUBROUTINE f_lammps_set_virial
+
+FUNCTION f_lammps_find_peratom_energy(i) RESULT(energy) BIND(C)
+  USE, INTRINSIC :: ISO_C_BINDING, ONLY : c_int, c_double
+  USE LIBLAMMPS
+  USE keepstuff, ONLY : lmp
+  IMPLICIT NONE
+  INTEGER(c_int), INTENT(IN), VALUE :: i
+  REAL(c_double) :: energy
+  REAL(c_double), DIMENSION(:), POINTER :: e
+
+  e = lmp%extract_compute('peratom', lmp%style%atom, lmp%type%vector)
+  energy = e(i)
+END FUNCTION f_lammps_Find_peratom_energy
+
+SUBROUTINE f_lammps_find_peratom_virial(v, i) BIND(C)
+  USE, INTRINSIC :: ISO_C_BINDING, ONLY : c_int, c_double
+  USE LIBLAMMPS
+  USE keepstuff, ONLY : lmp
+  IMPLICIT NONE
+  REAL(c_double), DIMENSION(6) :: v
+  INTEGER(c_int), INTENT(IN), VALUE :: i
+  REAL(c_double), DIMENSION(:,:), POINTER :: virial
+
+  virial = lmp%extract_compute('vperatom', lmp%style%atom, lmp%type%array)
+  v = virial(:,i)
+END SUBROUTINE f_lammps_find_peratom_virial
+
+SUBROUTINE f_lammps_fixexternal_set_vector() BIND(C)
+  USE, INTRINSIC :: ISO_C_BINDING, ONLY : c_double
+  USE LIBLAMMPS
+  USE keepstuff, ONLY : lmp
+  USE ext_stuff, ONLY : vec_length
+  IMPLICIT NONE
+  REAL(c_double), DIMENSION(vec_length) :: v
+  INTEGER :: i
+  DO i = 1, vec_length
+    v(i) = REAL(i, c_double)
+    CALL lmp%fix_external_set_vector('ext2', i, v(i))
+  END DO
+END SUBROUTINE f_lammps_fixexternal_set_vector
diff --git a/unittest/fortran/wrap_fixexternal.cpp b/unittest/fortran/wrap_fixexternal.cpp
index aa6cb2b921..694aceb009 100644
--- a/unittest/fortran/wrap_fixexternal.cpp
+++ b/unittest/fortran/wrap_fixexternal.cpp
@@ -23,6 +23,9 @@ void f_lammps_reverse_direction();
 void f_lammps_find_forces();
 void f_lammps_add_energy();
 void f_lammps_set_virial();
+double f_lammps_find_peratom_energy(int);
+void f_lammps_find_peratom_virial(double[6], int);
+void f_lammps_fixexternal_set_vector();
 }
 
 using namespace LAMMPS_NS;
@@ -128,10 +131,64 @@ TEST_F(LAMMPS_fixexternal, energy_peratom)
 {
     f_lammps_setup_fix_external_callback();
     f_lammps_set_fix_external_callbacks();
+    lammps_command(lmp, "compute peratom all pe/atom");
     double energy;
     lammps_command(lmp, "run 0");
-/* FIXME: the per-atom energy is NOT summed up by this function! We need
-   another test. */
-    energy = lammps_get_thermo(lmp, "pe");
-    EXPECT_DOUBLE_EQ(energy, 11.0);
+    int nlocal = lammps_extract_setting(lmp, "nlocal");
+    for (int i = 1; i <= nlocal; i++)
+    {
+        energy = f_lammps_find_peratom_energy(i);
+        if (i == 1)
+          EXPECT_DOUBLE_EQ(energy, 1.0);
+        else
+          EXPECT_DOUBLE_EQ(energy, 10.0);
+    }
+};
+
+TEST_F(LAMMPS_fixexternal, virial_peratom)
+{
+    f_lammps_setup_fix_external_callback();
+    f_lammps_set_fix_external_callbacks();
+    lammps_command(lmp, "compute vperatom all stress/atom NULL");
+    double virial[6];
+    lammps_command(lmp, "run 0");
+    int nlocal = lammps_extract_setting(lmp, "nlocal");
+    for (int i = 1; i <= nlocal; i++)
+    {
+        f_lammps_find_peratom_virial(virial, i);
+        if (i == 1)
+        {
+          EXPECT_DOUBLE_EQ(virial[0], -1.0);
+          EXPECT_DOUBLE_EQ(virial[1], -2.0);
+          EXPECT_DOUBLE_EQ(virial[2], 1.0);
+          EXPECT_DOUBLE_EQ(virial[3], 2.0);
+          EXPECT_DOUBLE_EQ(virial[4], -3.0);
+          EXPECT_DOUBLE_EQ(virial[5], 3.0);
+        }
+        else
+        {
+          EXPECT_DOUBLE_EQ(virial[0], -10.0);
+          EXPECT_DOUBLE_EQ(virial[1], -20.0);
+          EXPECT_DOUBLE_EQ(virial[2], 10.0);
+          EXPECT_DOUBLE_EQ(virial[3], 20.0);
+          EXPECT_DOUBLE_EQ(virial[4], -30.0);
+          EXPECT_DOUBLE_EQ(virial[5], 30.0);
+        }
+    }
+};
+
+TEST_F(LAMMPS_fixexternal, vector)
+{
+    f_lammps_setup_fix_external_callback();
+    f_lammps_set_fix_external_callbacks();
+    f_lammps_fixexternal_set_vector();
+    lammps_command(lmp, "run 0");
+    double *v;
+    for (int i = 0; i < 8; i++)
+    {
+      v = (double*) lammps_extract_fix(lmp, "ext2", LMP_STYLE_GLOBAL,
+        LMP_TYPE_VECTOR, i, 1);
+      EXPECT_DOUBLE_EQ(i+1, *v);
+      std::free(v);
+    }
 };