Sebi Chairman U K Sinha on Tuesday said he is hopeful of the government permitting the market regulator to access "call data records" of people being probed in alleged market irregularities.

"Request for call data record is being considered by the government. It requires a lot of consultations with other ministries... it will happen but will take some time before it is approved," Sinha told reporters in Mumbai.

Speaking on the sidelines of a function organised by CAMS, Sinha said that manipulative stock market activities have been vastly curtailed and Sebi is keeping its vigil.

Sebi has sought the government permission to access call data records of people under scanner for their role in alleged manipulative activities, especially for insider trading, to put across a strong case against such entities.

While certain government agencies have also got phone tapping power for investigative purposes, Sebi has not got access even to old records of telephone calls and it has to depend on other agencies for help in such cases.

On the probe into crash of mid-cap stocks on July 26, Sinha said that whatever complaint is there, they are being investigated.

"... certain manipulative activity happens in the market. But, it has been vastly curtailed. Sebi always has to remain active for this," he said.

On August 3, Sebi had barred 19 entities, including three individuals, in an interim order from securities till further orders. The move came after initial probe into share plunge of 20-26 per cent in four mid-cap stocks -- Parsvnath, Tulip Telecom, Glodyne Technoserve and Pipavav Defence -- on July 26.