The waste management company contracted to provide trash collection services in several Massachusetts cities and towns is accusing striking local union workers of resorting to outright violence as contract negotiations stall.

According to Republic Services, the Teamsters Local 25 has engaged in “criminal behavior” to include “slashing tires on occupied vehicles, harassing drivers out servicing customers, threatening employees and sabotaging trucks.”

The safety of the company’s employees, according to Republic Services Vice President Kurt Lavery, “is non-negotiable.”

“Teamsters’ actions are putting our drivers at risk as we serve customers. We are committed to good-faith negotiations, and we will not tolerate actions that endanger our employees or our communities,” Lavery said in a statement.

Union officials and company negotiators are meeting in the presence of a federal mediator, but apparently have not found middle ground since about 450 workers walked off the job on Tuesday.

The company says they “presented terms that addressed the union’s stated interests and could have resolved the contract dispute” that the union refused the deal without making a counter offer.

A spokesperson for Local 25 told the Herald that the company has been “lying through its teeth about this strike since it started.”

“The company’s assertion that its latest offer could have ended the strike is just the latest example of that. The proposal was a slap in the face to our members and completely unreasonable,” the spokesperson said.

The outside drivers, the union said, “are scabs.”

If the company were serious about ending the strike which began with the expiration of the union’s last contract, they would offer the striking Teamsters “improved benefits and a living wage,” according to Local 25.

Other waste management companies pay more and offer better benefits, and the union said in a statement on Thursday that Republic Services won’t answer their demands that they match the contract rates negotiated with the company’s competitors.

“Nothing we’ve been asking for since this strike began is inconsistent with what so many other workers in this industry are already getting. True leadership would prioritize labor peace and the needs of Massachusetts residents over corporate greed,” they said.

Local 25 President Thomas Mari said in a statement the union is holding strong on the picket lines.

“This strike is all about fairness, equity, and maintaining the area standards established by Local 25. I have never seen a group of workers who are so united and committed to making certain they are able to enjoy the same pay and benefits as people who are doing the exact same job at another employer,” he said.

The union did not offer a response to the allegations of violence and “criminal behavior,” however, this isn’t the first time they’ve faced such striking accusations.

Several members of the union were indicted — and later found not guilty — in 2015 over accusations they’d gone “rogue” the year prior and were employing “old school thug tactics” to shakedown a television production company for do-nothing jobs.

While most of the accused were acquitted, the union’s former business agent, Mark Harrington, offered a guilty plea to a charge of attempted extortion and received a six-month sentence of home confinement.