diff --git a/modules/sibyll/sibyll2.3d.f b/modules/sibyll/sibyll2.3d.f
index 8fccb7a42026eef3621cd80ef20797e27a65a4e1..49b1ad361addc8c8d04bbf8674bb02ef6cc412fc 100644
--- a/modules/sibyll/sibyll2.3d.f
+++ b/modules/sibyll/sibyll2.3d.f
@@ -6616,6 +6616,10 @@ C...Choose decay channel
 
       KD =6*(IDC-1)+1
       ND = KDEC(KD)
+      IF(ND.GT.10) THEN
+         WRITE(LUN,*) 'DECPAR: too many final state particles in decay!'
+         STOP
+      ENDIF
       MAT= KDEC(KD+1)
       MBST=0
       IF (MAT .GT.0 .AND. P0(4) .GT. 20.D0*P0(5)) MBST=1