Arlington Transit bus riders should see improvements to their service compared to last week, but they might also notice new drivers.

The old bus drivers who participated in last week’s strike are “locked out,” said Charles Smith, a representative of American Federation of State, County and Municipal Employees Local 3001. He said the new drivers replacing the old drivers are trainees.

“Absolutely no trainees were allowed to operate buses in revenue service,” said Bill Forsythe, chief executive of Forsythe Transportation, which is contracted to run Arlington’s ART bus service. “Only those professional bus operators who had passed our skills assessment and were trained on their routes have been allowed to provide revenue service for our client, ART,” he said in a statement.

About a quarter of Forsythe’s ART drivers did not show up for work June 13, causing major delays throughout the week. Those delays forced Arlington County Board member Chris Zimmerman to call for an end to the strike. As of Monday, the routes have been fully restored, Forsythe said.

Smith said the fight began when a union member wore a pin to work. That person was suspended. Drivers who participated in the strike, and therefore violated the no strike clause in their contract, have been suspended pending an investigation, Forsythe said, denying the lockout.

Members of the union also said they worked under horrible conditions, which included not being able to take a bathroom break and sexual harassment. The union filed a complaint on the harassment to the Arlington County Human Rights Commission, Smith said.