How to ompress the partition/subpartition of an index

 HI,
Does anyone know syntax to compress the INDEX partition/subpartition. I am trying the following but getting error :

SQL> Alter index INV_DET_TRAFFIC_TYPE_IDX rebuild
  2  subpartition SUBPART_1
  3  TABLESPACE DATA_IDX compress ;
TABLESPACE INDEX_TS compress
                             *
ERROR at line 3:
ORA-14189: this physical attribute may not be specified for an index subpartition

Just to test , I removed the TABLESPACE INDEX_TS clause but error remains the same.

PS : I don't want to drop and recreate index.

Best Regards,
Anurag