Maharashtra Navnirman Sena chief Raj Thackeray and other senior party leaders were detained Wednesday when they were proceeding to take part in the party's anti-toll agitation to Navi Mumbai.

 

 "Thackeray and other leaders have been placed under preventive detention. I cannot say when they will be released…maybe after the agitation ends," Pravin Salunkhe, a police officer, told media persons.

 

 A team of policemen halted Thackeray's motor convoy which was proceeding towards Vashi toll check post on the Mumbai-Navi Mumbai border to stop the toll collection.

 

 His wife, Sharmila Thackeray staged a sit-in demonstration outside the police station in Chembur, protesting the arrest of the senior party leaders.

 

 The preventive detentions came as the MNS's anti-toll agitation spread across the state since Wednesday morning with all major roads and highways being blockaded by thousands of party activists.

 

 Following the detentions, the home ministry ordered beefing up of security at all important places in the state to pre-empt any law and order situation.

 

 On the Aurangabad-Beed highway, minor violence erupted as some activists, purportedly of the MNS, pelted stones at buses and private vehicles to protest Thackeray's detention.

 

 Raj's cousin and another senior party leader Shalini Thackeray led an agitation of party activists near Dahisar toll post in north-west Mumbai.

 

 MNS activists, including representatives of its women's wings, stormed important roads and highways on the outskirts of Mumbai, Thane, Pune, Raigad, Nashik and other major cities, attempting to halt the morning peak-hour traffic.

 

 In some places, vehicle tyres were deflated to stop vehicular movement leading to traffic snarls.

 

 Police, accompanied by Rapid Action Force, were out in large numbers, stopping, catching and detaining hundreds of MNS activists.

 

 However, school vehicles and college students were not prevented by the activists and allowed to proceed to their institutions. Ambulances and vehicles of other essential services also were allowed to operate.

 

 Security has been beefed up at the 145 toll collection booths across the state, including five in Mumbai.

 

 In the past few weeks, activists purportedly of the MNS vandalised several toll booths in places like Kolhapur, Thane, Mumbai, Aurangabad and Pune.