The prosecution said Monday it is holding three more police officers in custody on suspicion of taking bribes from an owner of 17 hostess bars.

This raises the number of detained officers in relation to the bribery to seven. On April 2, four police officers were arrested for allegedly receiving bribes from Lee.

The latest trio, from police stations located in Gangnam, southern Seoul, received about 50 million won each in return for helping the bar owner avoid a crackdown on illegal bar operations.

The owner, Lee Kyung-baek, is known as the “emperor of hostess bars.”

The prosecution has requested an arrest warrant for the officers, claiming they could destroy evidence. It raided the house of the officers and searched their cars on Thursday.

The prosecution is investigating Lee as he has reportedly kept a list of police officers who allegedly accepted bribes from him.

Police are also trying to confirm the list by searching the prison where Lee is currently detained, while determining which officers had kept in contact with him.