The owner of a property management company was among four people found dead in North Dakota, police said.
Robert Fakler, 52, was among those discovered by officers responding to a medical call at RJR Maintenance and Management on Monday.
Lois Cobb, 45, her husband William Cobb, 50, and 42-year-old Adam Fuehrer were also identified as victims.
An investigation is ongoing but police have yet to name a suspect or determine a motive for the slayings.
All four victims were employees at the company, Mandan Police Chief Jason Ziegler said at a news conference on Tuesday.
He said the incident was “specific to the victims”, but declined to provide further details.
Chief Ziegler added there was no reason to believe there was any threat to public safety, but would not elaborate on how the victims were killed.
“We have deceased bodies, we have a homicide investigation and that’s all I’m going to give you on that,” Mr Ziegler said.
“We’ve got a lot of good leads, a lot of good information. We’re going to do our due diligence to try ad locate and find more information.”
Police are reviewing surveillance footage from several cameras in the building and the surrounding area, Chief Ziegler said.
Mandan police have asked local businesses to review their surveillance tapes for possible leads.
Mr Ziegler said the crime has been “devastating” for Mandan, a town of about 22,000.
“It’s very unusual for the state of North Dakota,” he said. “It’s really kind of surreal.”
According to the company website, RJR is a family-owned business that manages commercial and residential properties in Bismarck and Mandan. A statement posted to the RJR Facebook page on Monday said the company was closed for the day.
Employees of the company were questioned following the discovery, but have since been released, USA Today reports.