More than 100 pigs survived a truck crash in the Toronto area only to be marched to the slaughterhouse on foot shortly afterward as dozens of animal rights activists watched in a tense standoff with police on Wednesday.

Police said the truck crashed as it was turning onto a road beside Fearmans Pork plant in Burlington, around 7:30 a.m., which led to several pigs escaping and roaming nearby streets.

Staff Sgt. Peter Corner of Halton Regional Police said there were about 160 pigs in the vehicle, most of them remained pinned inside as workers from the plant slowly removed them from the toppled truck and walked them to the plant.

He said some pigs died in the crash, but didn't have an exact number. The truck driver suffered minor injuries.

Speed may have been a factor in the single-vehicle crash, Corner said, but the investigation is ongoing and he said no charges have been laid.

Witnesses said a woman currently on trial for giving cool water to hot pigs was arrested for crossing the police line several times.

Jenny McQueen said she was with Anita Krajnc, both part of the animal welfare group Toronto Pig Save, to "bear witness" to the animals on their way to slaughter.

"They used a ton of force," McQueen said.

"We tried to get through the police tape and the police grabbed all of us. Then they drag her out and she tries to get in again to document the pigs, they drag her out again, then they arrest her."

Corner said a protester was arrested for obstructing police, but wouldn't release the name of the individual.

A video McQueen took and posted online shows Krajnc being dragged back to the police line by officers, handcuffed and then put into a squad car.

The video shows officers pushing and shoving protesters who screamed back. Pigs can be heard squealing in the background.

"The pigs are injured, they are screaming, they are frightened, they should be taken to sanctuary," McQueen said. "It's devastating for us to see this."

Krajnc posted a video on Facebook that appeared to show her in the back of the squad car.

"I'm currently speaking to you from a cab in a police car and the pigs are being herded off to the kill floor," she said. "They should be shown mercy and not being herded to the gas chambers."

Krajnc was in court on Monday. She has pleaded not guilty to a mischief charge in the June 2015 incident, when she poured water through the portholes of a truck carrying the pigs to the same slaughterhouse involved in Wednesday's crash.

She told court that feeding bacon to children is tantamount to child abuse, comparing the popular breakfast staple to cigarettes.

Fearmans could not immediately be reached for comment.