SHIMLA: The CBI on Tuesday arrested eight policemen, including an IPS officer IPS oficer , for the custodial death of one of the accused in the sensational gang rape  and murder of a schoolgirl in Shimla district last month, an official said.

The arrested included Inspector General of Police (IGP) Zahur H.Zaidi, who was heading the Special Investigation Team probing the crime, Deputy Superintendent Manoj Joshi, and former Station House Officer Rajinder Singh, a Sub-Inspector.

Others arrested are Assistant Sub-Inspector Deep Chand, Head Constables Surat Singh, Mohan Lal, and Rafiq Ali and Constable Ranjit Streta.

The policemen were on Tuesday afternoon sent in CBI custody till September 4 by a Special Central Bureau of Investigation (CBI) court in Shimla.

"Eight policemen, including IGP Zahur H. Zaidi, were arrested in connection with the custodial death of an accused," CBI Spokesperson Abhishek Dayal told IANS on phone from New Delhi.

Police said the 16-year-old schoolgirl was offered lift in a vehicle by prime accused Rajinder Singh on July 4 when she was returning home from school in Kotkhai town, nearly 56 km from the state capital.

On the way, the accused and his accomplices raped and murdered her in a nearby forest. Her naked body with injury marks was found two days later.

Rajinder Singh, Ashish Chauhan, Subhash Bisht, Deepak Kumar, Suraj Singh, and Lokjan were arrested. They were believed to be drunk at the time of the crime.

The case got a new twist after Nepal national Suraj Singh was allegedly strangled by 32-year-old accused Rajinder Singh in Kotkhai police station lock-up on July 19.

What happened at the police station remained a mystery because the two were housed in adjacent cells with minimal security.

Following the gang rape and murder of the girl, people held massive protests in the hill state. The victim's family alleged that the "real culprits" belonging to high-profile families had gotten away "scot-free".

Later, on the state government's plea, the Himachal Pradesh High Court recommended a Central Bureau of Investigation (CBI) probe. Earlier, the Special Investigation Team of the state police was handling the case.

Pulling up the CBI over the slow pace of investigation, the High Court on August 17 granted it two more weeks to complete the probe.

A Division Bench of Acting Chief Justice Sanjay Karol and Justice Sandeep Sharma also made all policemen of the Special Investigation Team as respondents in the case.

On court orders, the CBI constituted a Special Investigation Team headed by a Superintendent of Police after registering a case of murder and rape under the Indian Penal Code, apart from Protection of Children from Sexual Offences Act.

The CBI also registered a separate FIR to probe the circumstances leading to the death of Suraj Singh.