Human rights lawyer and pro tem secretary-general of Parti Reformasi Insan Malaysia (Prim) P Uthayakumar (photo) was today arrested by the police for allegedly threatening police officers over their handling of an investigation of a death in custody.

Uthayakumar, a tough campaigner against police brutality, was arrested by a team led by Selangor CID chief SAC Abu Bakar Mustafa at the Sepang Magistrate's Court at 4.20pm and taken to the town's police station.

Chairperson of Prim's police watch and human rights committee RN Rajah told malaysiakini the arrest took place at the end of the three-month-long inquiry into the custodial death of 19-year-old S Tharmarajen (photo).

"Uthayakumar was met by a group of police officers at the entrance of the courtroom and was told that he was arrested," he said.

Uthayakumar was representing the victim's family in the inquiry. They claimed that Tharmarajen died last June 21 due to beatings he suffered while in police custody.

Government doctors diagnosed pneumonia or tuberculosis as the cause of death.