MONTPELIER, Vt. (AP/WOOD) — A growing number of police departments across the country are taking action over concerns that carbon monoxide fumes from Ford Explorer patrol vehicles are seeping inside the SUVs, potentially sickening officers.

Vermont State Police and several other departments in the Northeast are inspecting their fleets or have installed carbon monoxide monitors in the vehicles. At least two departments in Texas and one in Massachusetts have gone further, pulling some or all their Ford Explorers off the road.

Ford Motor Co. has promised to repair the vehicles as it continues to investigate the cause of the problem.

“Police officers should be concerned, particularly this time of year,” said Dennis Slocumb, with the International Union of Police Associations, which represents more than 100,000 law enforcement personnel. “It could be a life-and-death issue if somebody lost consciousness while they were driving a police car down a highway. It could result in terrible tragedy.”

Authorities in Auburn, Massachusetts, confirmed an officer who passed out behind the wheel of his cruiser and crashed had tested positive for exposure to carbon monoxide. In a post on its Facebook page, the department said a total of three officers were hospitalized for “high carbon monoxide levels.”

The department also said it had taken 12 Explorers out of service over carbon monoxide concerns, including SUVs used by the city’s public works director and assistant fire chief.

“We would urge other departments to have their cruisers tested and/or purchase detectors to ensure everyone’s safety,” the department said.

Ford spokeswoman Elizabeth Weigandt said Thursday it has sent engineers to Auburn to inspect the vehicles and will go “to any department that asks for assistance.” It also sent inspectors to Wichita, Kansas, Austin, Texas, and several other departments.

In several cases, Ford found gaping holes had been drilled into the backs of Explorers after they were delivered to police departments, Weigandt said. The holes were used to install equipment, such as additional radios. They weren’t properly sealed, allowing carbon monoxide to enter the vehicle, she said.

“To address police customers who drive modified vehicles in unique ways, we are covering the costs of specific repairs in every Police Interceptor Utility that may have carbon monoxide concerns, regardless of modifications made after leaving Ford’s factory,” Weigandt said.

The Grand Rapids Police Department began switching to the Ford Police Interceptor SUV in 2014. However, Grand Rapids authorities said they’ve monitored the situation and have been assured that their vehicles are safe and not impacted by the issue.

Ford has not found elevated levels of carbon monoxide in Explorers sold to the general public, Weigandt said.— Associated Press Auto Writer Dee-Ann Durbin in Detroit contributed to this report.