Lucknow, May 9 (IANS): Six Uttar Pradesh policemen were Wednesday booked for the murder last year of a sub-inspector, police said.

According to police, the case is related to the death in May last year of sub-inspector Manoj Singh under mysterious circumstances in the Nagar Bazaar area of Basti, around 180 km from here.

Officials said a probe found the policemen guilty of conspiring to kill and of being actively involved in the murder of Singh.

The six policemen had earlier claimed that Singh died on May 29, 2011, when his service revolver accidentally fired while he was cleaning it.

Family members of Singh, however, had cried foul and had alleged that he was murdered in cold blood.

They had petitioned senior officials after which a departmental probe was ordered.

The investigation concluded recently and found that the six policemen posted in the Nagar Bazaar police station were behind Singh's death.

Following this, the police filed a case of murder against the cops.