The Central Bureau of Investigation (CBI) on on Thursday issued summons to Gujarat home minister Amit Shah for questioning in the Sohrabuddin Sheikh fake encounter case.
Shah, a key aide of Gujarat Chief Minister, Mr Narender Modi, has been asked to appear before the CBI's office in Gandhinagar by 1 pm on Thursday.
Three IPS officers from Gujarat and one from Rajasthan police are already in jail for their role in the case.
Sohrabuddin and his wife were killed in allegedly a fake encounter in 2005.
In March 2007, police said that Sohrabuddin Sheikh, belonged to the Pakistan linked terrorist group Lashkar-e-Tayyaba and was planning to assassinate Gujarat Chief Minister, Mr Narendra Modi, to avenge the death of Muslims killed in the 2002 Gujarat riots.
The government also admitted that Sohrabuddin's innocent wife Kausar Bi had been killed by the police and her body burnt in an attempt to remove traces of the crime.
The Gujarat Government admitted that senior police officers were directly involved in the killing of Sohrabuddin, and his wife, Kausar Bi, in 2005.
The admission came as a result of the intervention of Supreme Court, which ordered investigations into this case.
The CBI took up the case on directions of the Supreme Court. Earlier, the apex court had asked the CBI to probe if there was any larger conspiracy to the killings and submit the report by July 31.