The wheels on Detroit's buses are going around again.

Buses were back in business Tuesday morning after a one-day drivers' protest.

About 150 drivers held a rally Monday outside Detroit City Hall to demonstrate against what they say are a series of on-the-job attacks on drivers. The city halted bus service early Monday after drivers called in sick.

Local union President Fred Westbrook says that in the past week, two drivers were stabbed, one came under attack from three passengers and one had urine thrown on her.

Detroit city official Gary Brown says that the union members voted 2-to-1 last week to reject a proposed contract with the city and says the timing of the sick-out is "no coincidence." 
But the union said it wasn't behind the job action and couldn't do anything if drivers call in sick.

Detroit Police Chief James Craig said a special police unit soon will put officers on DDOT buses.

Moreover, new security cameras will be placed on the buses.