Senegal ? Street vendors protesting an attempt to clear them from the center of Senegal’s capital clashed with police Wednesday, throwing rocks at officers who fired tear gas to disperse the crowd.

Bands of young men burned tires in a few spots downtown, while others marched in small groups through a central market. Witnesses said most groups numbered about 60 or 70, seen in four or five neighborhoods of the city.

“We can’t wait for the government to find other places for us to sell our merchandise. We don’t have the time, and we don’t know what to do,” said Balla Ba, one of the demonstrators.

Riot police fired tear gas and chased down protesters, arresting some of them. A government office building and the offices of the city’s electric company caught fire in the melee. Firefighters had put out the blazes by afternoon.

The violence prompted the government to cancel a permit given to the city’s transport unions for a planned march. About 600 people marched anyway, facing off against riot police.

“We are going to march by force!” shouted union official Mademba Sock as he led the crowd demanding higher wages. Tear gas grenades followed, and an Associated Press reporter saw police beating a number of protesters with batons.