CHANNELVIEW, Texas (AP) — Texas police on Wednesday ripped apart the cab of a tractor trailer and pulled the truck’s driver out after pursuing him in a slow highway chase that shut down the road for hours.

The dramatic confrontation on a stretch of highway east of Houston came hours after sheriff’s deputies began trying to pull over the truck, which could be seen on television news footage crawling along the interstate. The driver’s arrest left questions about what prompted his behavior and the heavy police response.

Deputies finally brought the 18-wheeler to a stop on the shoulder of Interstate 10 using spike strips to puncture its tires.

For hours, the driver had ignored police commands to exit and continued to rev the engine of the disabled vehicle, Harris County Sheriff Ed Gonzalez said. Even after it was stopped and surrounded by police cruisers and armored vehicles, one wheel of the truck could be seen continuing to spin in its punctured tire.

Police eventually used a bulldozer-like vehicle to pulverize the cab before sending a dog into the truck and then pulling the driver out at around 4 p.m. In TV footage, officers could be seen walking the man to a stretcher, his face bloodied.

Gonzalez said the driver continued to press the gas and hold on inside the cab as officers tried to drag him out. He said the driver appeared to be suffering from “heavy impairment” but that authorities don’t know what was behind his behavior.

“Still don’t know why he was reacting in the erratic manner he was,” Gonzalez said. He did not identify the man by name.

The container the truck was pulling was empty, the sheriff said.