Anti-government protesters planned another rally at Din Daeng intersection on Tuesday evening, according to Bangkok police, after 11 demonstrators were arrested there on Monday
Pol Maj Gen Piya Tavichai, deputy commissioner of the Metropolitan Police Bureau, said the Thalu Gas group had invited supporters online to a rally at Din Daeng intersection in Din Daeng district on Tuesday evening.
Police did not know when the protest would start.
Units were already mobilised to maintain order there, he said.
According to Pol Maj Gen Piya, the Thalu Gas group began a rally at the intersection on Monday at 6pm. Demonstrators either threw or fired marbles, fireworks and mini-bombs at police and scattered spikes on the road.
He alleged they set fires at tunnel ventilation fans and control cabinets, and other objects, on Vibhavadi Rangsit Road.
He said police moved against them at 8.30pm and over the next hour arrested 11 demonstrators and seized improvised explosive devices, catapults and marbles.
Earlier, on Monday afternoon, police arrested a man identified as Watcharakon Taweesinsoontron in Rayong province for falsely claiming on Facebook on Sept 8 that a demonstrator had died after being hit by a crowd control vehicle, Pol Maj Gen Piya said.
The injured demonstrator was alive and received treatment at Police General Hospital. The false assertion was aimed at drawing more people to rallies, according to Pol Maj Gen Piya.
Since July, 522 of the 767 protesters who were wanted by police for violations of the law had been arrested, Pol Maj Gen Piya said.