Agitating transport workers last night damaged about a dozen vehicles and set fire to a police box and a wrecker, prompting police to use teargas shells and charge batons to control the situation.
Four policemen and at least eight other people were injured in the ensuing clash.
Eight of the victims, including the four cops, were admitted to Dhaka Medical College Hospital shortly after midnight.
Hundreds of cars, pickups and bikes trying to enter and exit the capital got stranded on the road stretching from Aminbazar to Savar, as several hundred transport workers blocked the Gabtoli Road around 7:30pm.
Police said the transport workers threw brickbats at them when they tried to prevent the protesters from damaging vehicles.
In response, police fired teargas canisters and used batons to disperse the protesters.
Rab members were called in to prevent further clashes.
Some 200 Chhatra League activists from Govt Bangla College went to the spot and took position on Gabtoli Road around 9:30pm.
They chanted slogans against the transport workers' strike in protest against two court verdicts that sentenced a bus driver to life and a truck driver to death over the deaths of several people in road accidents.
Local lawmaker Aslamul Haque went to the spot to pacify the transport workers around 10:00pm.
But the workers told him they would not sit for discussion until the court verdicts were withdrawn.
Some workers even threw brickbats at the lawmaker, forcing him to retreat, witnesses said.