Authorities raided the home and office of a Michigan doctor who is suspected of performing illegal abortions after 14 containers of human tissues were found in his car trunk.

Authorities accidentally discovered the controversial cargo after Dr. Michael Arthur Roth of West Bloomfield, Michigan, figured in a road accident two weeks ago when Roth hit a child who became critically injured, according to 7 Action News.

After Roth's car was impounded, a search of the car yielded plastic containers and medical equipment.

A large amount of the painkiller Fentanyl was also found in the trunk, according to the Detroit Free Press.

West Bloomfield Deputy Chief Curt Lawson said his department, the state Attorney General's Office and Drug Enforcement Agency (DEA) are conducting the investigation. Detroit Free Press did not name the doctor in its report.

"This is related to items that were found in the vehicle," Lawson said. "Yesterday we did conduct two raids, one at his office and one at his home in West Bloomfield."

Lawson said they took the car back to the police department. "That's when the bottles and evidence were found in the trunk area of the vehicle," he said.

He said possible human tissues and drugs were found. The human tissues were brought to the Oakland County Medical Examiner's Office for examination.

"We do have an opinion from the medical examiner's office that this is remnants of conception, but there was nothing that was seen within the containers that were recognisable," Lawson said.

Fox News reported that Roth is a primary doctor at Novi Laser & Aesthetic Center in Novi, Michigan.

At least six malpractice complaints and judgments have been posted against Roth from 1988 to 2015 including home abortions.

"He has a long and sordid history," Right to Life of Michigan's legislative director Ed Rivet said. "This isn't just like, 'Oh wow, this guy all of a sudden did something off the legal or ethical path.' This has been a whole career of this stuff."

In 2002, a state health inspector found that Roth's drug-control license had expired for more than 20 years previously and the doctor was placed on professional probation for six months, fined $15,000 and prohibited from performing abortions outside a clinical setting.

Roth was also fined $2,000 and sanctioned by a state disciplinary committee in 2012 for different violations.

In a 1988 New York Times article, Roth said was quoted as saying, "I think that abortion should be available on demand."

"I haven't turned anybody down," he added.

Roth has not been charged and the police are still investigating the case.