Trouble broke out at Singur in West Bengal's Hooghly district on Sunday when police had to burst tear gas shells to disperse a mob that damaged a watch-tower near the project site of the Tata Motors' automobile manufacturing unit where construction work was underway. The mob allegedly hurled bricks at the police when challenged, injuring some of them. Additional security forces were rushed to the area, a senior district police official said. Those responsible for the disturbance had broken out from a victory procession taken out by local leaders of the Trinamool Congress that won the panchayat polls held earlier this month, a senior State official said. The incident occurred hours ahead of a visit there by Trinamool Congress Chief Mamata Banerjee, to pay respects to those who died during the agitation led by her party against the acquisition of farmland for the Singur project. After the good showing put up by her party in the area in the rural polls Ms. Banerjee has reiterated her demand that Tata Motors return the 400 acres of land she claims was forcibly acquired from peasants in Singur. In all, about 997 acres have been acquired. Veteran Marxist leader Jyoti Basu said here that there could be discussions to raise the level of compensation to those who claim their plots were taken away without consent. But if there were attempts at sabotage to close down the project, the message to the people would be that the Trinamool Congress was against development.