Mumbai: A team of National Security Guards (NSG) from Delhi would arrive here on January 28 to assist in the probe into the January 27 night explosion at suburban Vile Parle, even as police tightened security measures in view of Prime Minister Atal Behari Vajpayee's visit.

The NSG team would co-ordinate with forensic experts to determine the type of explosive that was used in the blast that left 30 persons injured, assistant commissioner of police (ACP) Vivek Jadhav said.

Forensic experts have already drawn samples of the explosives used in the blast.

Police, however, suspect it to be a crude bomb and were on the lookout for a bicycle rider, who was suspected to have dropped the explosive, he said.

Meanwhile, security has been tightened in view of the Prime Minister's visit. Police resorted to 'naka bandis' and stepped up combing operations besides keeping vigil at strategic locations.

Deputy Chief Minister Chhagan Bhujbal visited the explosion site to get the first hand information of the blast. Chief Minister Sushilkumar Shinde, who was in Pune, rushed to Raj Bhavan and is stated to visit the site later.

According to ACP Jadhav, of the 30 injured in the blast, 29 were admitted to Cooper Hospital, Nanavati Hospital and KEM Hospital, while one was treated and discharged.

Some of the injured were in a serious condition, he added.

PTI