Romanian bombs

The IAR.93 was said to use the BE-50, BE-100, BEF-100, BEM-100, BM-250, BEM-250, BA-500, BE-500, BM-500 GP bombs and CL-250 cluster bombs.

The only info I can find is the CL-250 uses the BAAT-10 and BF-10F AP bomblets and is similar to the RBK-250.

The Bx-50/100/250/500 series seem like FAB-50/250/500 produced locally.

Any ideas on whate the BE, BEF, BEM, BM, BA mean?