Baba Siddique, a former Maharashtra minister and member of the Ajit Pawar faction of the NCP, has been shot at in Mumbai's Bandra and rushed to a hospital, where his condition is said to be critical.
Sources said three bullets were fired at Mr Siddique around 9.30 pm on Saturday at the office of his son Zeeshan, who is the MLA from Bandra East. Two people have been taken into custody.
Mr Siddique is undergoing treatment at the hospital. Sources in the hospital said at least one of the bullets hit Mr Siddique in the chest and he is being given continuous cardiopulmonary resuscitation (CPR).
Mr Siddique, who was a three-time MLA from Bandra West, was associated with the Congress for 48 years and had quit the party in February and joined Ajit Pawar's NCP. Zeeshan Siddique was expelled from the Congress in August.
The firing took place on Dussehra and came months ahead of the Maharashtra Assembly elections, which are expected to be held later this year.
Expressing his shock, NCP Spokesperson Brijmohan Shrivastav told NDTV that Mr Siddique had not spoken about any threats from anybody.
Mr Siddique was elected as an MLA from the Bandra West constituency in 1999, 2004 and 2009 and served as a minister of state for food and civil supplies, labour and FDA between 2004 and 2008.
The former MLA is known not just for his political acumen but also for hosting lavish parties. A cold war between superstars Shah Rukh Khan and Salman Khan was resolved at an iftaar party hosted by Mr Siddique in 2013.