ROCHESTER, N.Y. — Drivers and managers at First Student Bus in Rochester started the week with a mess on their hands.

Fire extinguishers were used to vandalize more than 30 buses in the company’s East Main Street lot early Monday morning.

'Tthey took the fire extinguisher and they sprayed it all inside the bus," said driver Tonia Foster. "You could see it on the ground right there.”

The vandalism delayed bus arrival on the morning anywhere from 10 to 30 minutes. First Student teamed with the school district to contact families via an automated call at the five Rochester schools and two city charter schools whose students would be late.

Bus drivers did their best to clear the liquid carbon dioxide from the seats, windshields and cameras.

"It was hectic, but we worked together," said driver Charlie Ross. "We had to clean our buses. I had to clean my bus. But unfortunately, it came back after it dried."

Remnants of the liquid CO2 reportedly remained inside the buses as they delivered students. While First Student management praised its drivers for their response, one union driver questioned whether the buses were safe to transport students.

"I have a couple of my drivers saying their throats are hurting," said union shop steward Michelle Vega. "Couple of them are hurting on their skin. They did the best they could to clean it for what we need. But we need cameras and we need higher fences so this activity doesn’t' continue. Because this is for the safety of our children and our drivers."

Monday's mischief is the second attack this month on First Student's fleet. Vandals hit buses serving Brighton earlier this month.

The Rochester Police Department continues to work with the Cincinnati-based company and the city school district to find those responsible.