The Mumbai police on Tuesday nabbed an accused in the blast in a local train while it was entering Mulund station.
Aatib Nasir Mullah, a resident of Padgha village in Thane district, was arrested near the Bandra-Kurla complex, Joint Commissioner of Police (Crime), Dr Satyapal Singh told PTI.
"Police is interrogating him to get more details regarding the exact nature of his role in the incident," he said.
Mullah is the second person to be arrested in the case after another accused Saquib Nachan surrendered before Mumbai police on April 10.
He is accused of engineering the blast in a local train on March 13, killing 11 people and has been detained under the Prevention of Terrorism Act (POTA).
Nachan's father had filed a petition in the Mumbai High Court alleging that the police wanted to kill his son in an encounter.
The high court had, however, asked Nachan to surrender at the earliest.
Crime Branch officials, meanwhile, on Monday interrogated four youths from Bhiwandi over their role in the Mulund blast, police sources said adding four to five persons could be arrested in this connection.
More from rediff