A gunman opened fire inside a Minneapolis sign-making business killed four people before fatally shooting himself, police said early Friday.

The victims’ bodies were found shortly after officers arrived at Accent Signage Systems Inc., located in a residential area of the city’s north side, after receiving a 911 call Thursday afternoon, according to an article from The Associated Press.

“When officers arrived and entered the business to assist with the evacuation of employees, give aid to the victims and to search for the suspect, they found four victims dead from apparent gunshot wounds,” according to a statement from police spokesman Sgt. Stephen McCarty.

Four other people were wounded in the shooting, including three critically, the article says.

No details have been released about the shooter, other than he was found dead from an apparent self-inflicted gunshot wound, AP reports.

During a news conference Thursday night, Minneapolis Police Deputy Chief Kris Arneson wouldn’t specify how many people had been killed, saying only that “several” victims were found dead inside, AP says. She also said that police never fired at the shooter, but she did not release the shooter’s possible motive or whether he had worked at the company.

None of the victims’ names has been released.