(CNN) — A shooting at a St. Louis business Thursday that left four people dead appears to be a murder-suicide, a police official said.
After a review of evidence, including a surveillance video, officers determined there had been an argument in the office of a home health care business, Capt. Michael Sack told reporters.
It was unclear whether the “brief” argument carried over from another day, Sack said.
The victims were two women and two men, described as being in their early 40s to mid-50s, police said. One of the men, possibly an owner, was the shooter, Sack said.
All of them were believed to be employees.
A semi-automatic handgun was recovered.
No other people were injured, officials said.
The shooting occurred at the Cherokee Place Business Incubator, CNN affiliate KTVI reported.
Police have not been able to find any witnesses to the shooting, according to Sack.
After receiving a call at about 1:30 p.m., police rushed to the building, which houses several businesses.
Emergency responders said “multiple victims” were reportedly shot at a St. Louis, Missouri business.
The shooting happened Thursday afternoon, June 13, 2013.