Ex-IPS officer O P Mathur, who was the state CID chief when it first probed the Sohrabuddin fake encounter case, was today questioned by CBI which also made another attempt to get former minister Amit Shah's remand by approaching the Gujarat High Court.

Mathur, who is now in-charge of Gujarat government's Rasksha Shakti University, presented himelf before the CBI for questioning at its office in Gandhinagar after he was summoned by the agency on July 27. He had failed to appear on that date citing personal reasons.

Mathur was the head of state CID which investigated the encounter of Sohrabuddin and alleged murder of his wife Kausarbi in November 2005, before the probe was transferred to CBI by the Supreme Court in January this year.

CBI sources said they would be able to get valuable inputs from Mathur in connection with the case. He was earlier summoned by CBI in May but his statement was not recorded at that time.

The CBI also challenged in the High Court the order of lower court rejecting its plea for remand of Shah in connection with the Sohrabuddin case.

A petition in this regard was filed in the High Court by the CBI today, sources said.

CBI's plea for 10-day custody of Shah, a former minister of state for home, was rejected yesterday by the court on the ground that the probe agency does not have substantial grounds to seek his remand.

Additional Chief Judicial Magistrate A Y Dave rejected CBI's application saying the agency was earlier given time to question Shah inside jail for three days, but it quizzed him for only for three hours. Hence, the CBI demand for Shah's remand cannot be entertained, the court said.

The CBI had demanded custody of Shah, saying that he did not cooperate during interrogation in jail.

The court had further said the grounds for seeking Shah's remand given by the CBI in a sealed cover on Monday last, were "like general allegations".

"In light of the constitutional rights of the accused, based on this short note (by CBI), to assume primarily that (Shah) is an accused would not be proper," the court said.

"In view of the facts, also there are no substantial grounds with the CBI to seek remand of the accused (Shah)," it had further said.

The Central probe agency has already recorded the statement of another retired IPS officer G C Raigar, who also headed the state CID when it was probing the fake encounter case. He was called in as a witness.

The CBI has also summoned former investigation officer in the case, Geetha Johri who has been asked to appear before the agency by August 10.

The Central agency arrested Shah on charges of criminal conspiracy, murder, kidnapping and extortion on July 25.