Ukraine's anti-corruption bureau launches case against sister agency

KIEV (Reuters) - Ukrainian investigators on Tuesday said they had opened a criminal case into suspected extortion by officials at a sister anti-corruption agency, based partly on information from a whistleblower who also implicated the president's office.

The National Agency on Corruption Prevention (NAZK) is a keystone of Western-backed reforms but has been criticised for making slow progress with its main task of verifying officials' wealth declarations for evidence of ill-gotten gains.