The accused were picked up from a bungalow last evening where they had assembled allegedly to plot the killings, said inspector VR Andale of Kalyan taluka police station.
One of the accused, identified as Nasruddin S Shaikh, a builder, had a business-related dispute with Jakki Fakurde and Ravi Patil, also builders, and allegedly planned to bump them off with the help of others.
The remaining accused are identified as Juber, Sameer Ahmed Khalil Khan, Afzal Ahmed Ayud Shaikh and Chandan Harish Mishra.