Six people were shot and killed and several others wounded in Michigan on Saturday night in a series of apparently random shootings, according to authorities who said they had the suspected gunman in custody.

The Kalamazoo Department of Public Safety said on its Facebook page that six people had been shot and killed and several others seriously wounded in three shootings in Kalamazoo County, in southwest Michigan.

"We seem to be dealing with a worst-case scenario, someone driving around shooting," Kalamazoo County Undersheriff Paul Matyas told NBC News earlier. At least three people were wounded in the attacks.

Early on Sunday WWMT television said on its website a "strong suspect" was in custody, citing Kalamazoo Public Safety Chief Jeff Hadley.

Matyas also told a Fox News affiliate "the threat to the public is over. We now have our suspect". The suspect was not identified, but media reports, citing police, said he was aged 45, from Kalamazoo.

The public safety department earlier described the gunman  as a white male in his 50s who was believed to be driving a dark colored Chevy HHR SUV with chrome wheels, adding that the vehicle may have been damaged.

Police said the man who was arrested was driving a black HHR and had a weapon in the vehicle.

According to local media, four people were shot dead at a  Cracker Barrel restaurant in Texas Township, and two more died at a Seelye Kia dealership in Kalamazoo.

The carnage began early Saturday evening when Matyas said police were first called to a Kalamazoo County apartment building where a woman was shot multiple times before later being listed in serious condition.

Hours later, they were called to the car dealership where two people were shot and killed, and a third was wounded.

Four people were killed at a third shooting scene in the Cracker Barrel parking lot, where the gunman opened fire on people in their cars after a brief conversation. A fifth person there was critically wounded, Matyas said.

The victims and shooting scenes appeared to have no link apart from the suspect. No motive for the seemingly random shootings had been determined.

Authorities could not be reached to verify the reports independently, but confirmed the deaths in media interviews.

The victims' identities were not released. One local report said the dead included an eight-year-old boy, but others later said the child was among those wounded.