Islam was taken into custody from near the Paroma Island on the Eastern Metropolitan Bypass after CPI(M) demanded his arrest for masterminding the attack on Mollah at Kantatala, police said.
Mollah, who was attacked on January 6, is admitted to a private hospital here.
Islam was admitted to a private nursing home at Rajarhat on January 8 after CPI(M) cadres allegedly fired at his vehicle and attacked him at Bamanghata in the district.
In a virtual indictment of the state government, West Bengal Governor M K Narayanan had said that goondaism was taking place in the state.