Indian police have arrested a fourth suspect in the Mumbai, formerly known as Bombay, serial blasts that killed nearly 200 people and wounded 800 others earlier this month.

Police picked up a doctor of traditional Indian medicine and resident of Mumbai, Tanvir Ansari, late on Sunday.

The chief of Mumbai's anti-terrorism squad said authorities believed Ansari had gone to Pakistan in 2004 where he learned how to make bombs and how to use arms and ammunition.

Indian news agencies quoted unnamed anti-terrorism officials as saying that he had links to the Pakistan-based Kashmiri separatist group known as Lashkar-e-Toiba. The group has denied any involvement in the bombings in Mumbai.

The other three suspects, all Indian Muslims, were arrested last week for their alleged role in the rush-hour blasts which ripped through packed commuter trains during the evening rush hour.

Some information for this report provided by AP and AFP.