Kolkata, March 8 (IANS): The Central Bureau of Investigation (CBI) will approach the Basirhat Sub-Divisional Court in North 24 Parganas district in West Bengal on Saturday to seek the extension of its custody for Trinamool Congress leader Sheikh Shahjahan, the accused mastermind of the January 5 attack on ED and CAPF sleuths in Sandeshkhali.

Sources said the principal argument of CBI will be that their sleuths hardly got time to interrogate Shahjahan after it got his custody from the CID-West Bengal on the March 5 evening.

After being arrested on February 28 late night, Shahjahan was first presented at the Basirhat Sub-Divisional Court on the next day, which remanded him to ten days of police custody. The tenure of that custody is scheduled to expire on Saturday.

Meanwhile, on Friday morning, a team of CBI officials escorted heavily by armed personnel of the Central Armed Police reached the residence of Shahjahan in Sandeshkhali, in front of which the attack on ED and CAPF personnel had taken place.

The combined CBI-CAPF team, according to sources, is 50, and special security precautions have been taken. A couple of members from the forensic department are also accompanying the team, sources added.

Meanwhile, sources aware of the development, said that during the last two days of CBI custody, Shahjahan has started cooperating with the investigating officials during the course of interrogation.

The accused was being confronted with the details of the call lists of two of his mobile phones through which he had been constantly interacting with his close associates just before the attack on ED and CAPF personnel.

As per documents available with the CBI sleuths, the accused made 28 phone calls from these two mobiles within a span of 30 minutes before the attack took place on January 5.