The accused had allegedly organised an attack on Thane Shiv Sena leader Rajesh Ghatge in July this year, the officials of the anti-extortion cell said.
The 13 accused were arrested separately during the last month, following which police slapped the Maharashtra Control of Organised Crime Act (MCOCA) on them yesterday, police said.
Ghatge was allegedly attacked with a chopper and fired at from a revolver by the accused over some old enmity, police said.
He survived the attack and was admitted to a local hospital where he recovered.
The accused also have past criminal records against them in Thane, Mumbai and Navi Mumbai, police added.