A school bus driver for Westborough Public Schools was arrested on drunken driving charges early Thursday during her morning route, police confirmed.

Westborough police made contact with the bus driver, later identified as Jane Welch, 51, of Marlborough, at 7:40 a.m. at 135 East Main St., which is the Park Village West Apartments. Police said 25-30 students who had just been picked up at the complex were on the bus at the time.

Officers were dispatched after the bus company “called reporting the operator of the bus was slurring their words prior to getting on the bus,” according to a police report.

Officers found the bus parked on a public way at the apartment complex, with Welch at the wheel with children inside.

“I walked over to the bus and knocked on the window. A female opened the door to the school bus, who was later identified as Jane Welch. As the door opened, l noted a slight odor of an alcoholic beverage emitting from inside of the bus,” an officer wrote in the police report.

The responding officer also noted in the report that Welch was off balance, her speech was slurred as if “speaking with a thick tongue,” she had bruising on her face, glassy eyes and her makeup was “smeared all over” as if she “had difficulty putting on her makeup this morning.”

The bus was not running at the time, but the key was in the ignition, according to the police report. Welch was taken into custody after officers said field sobriety tests indicated she was intoxicated, according to the police report.

Giovanna Conde, a 12-year-old student at the Mill Pond School, said Welch was yelling at students on the bus Thursday morning and was clearly not acting like she usually does.

"'You guys think your life is hard? No, my life is harder!' And it was just really sad," Conde said. "I was kind of traumatized. I'm still feeling kind of shaken up about it."

The bus company said other drivers tried to stop Welch from getting into her bus earlier after they noticed her speech was slurred and saw her trip, a representative of the bus company told police, according to the report. The company was able to reach Welch on the bus radio and got her to stop and park the bus.

In a memo to the school community, Westborough Public Schools Superintendent Amber Bock said students were on the bus when Welch was arrested; however, officials believe Welch was arrested before driving with children onboard.

"We have told NRT, our bus company, that we are outraged that this happened, and we have demanded a full investigation into their procedures," Bock wrote.

Welch was charged with operating under the influence second offense, negligent operation of a motor vehicle and child endangerment while operating under the influence. Welch was held on $10,000 cash bail after her arraignment in Westborough District Court.

Welch has a previous operating under the influence charge in 2000.

Welch's employer, NRT Bus, said she has been fired.

"The safety of our students is critical, and we are deeply disturbed by these allegations. The driver has been terminated and we will continue to fully cooperate with local authorities while this matter is investigated," an NRT Bus spokesperson said in a statement.