Police were telling people to stay inside as they responded to a home in the 3200 block of Hunter Path in McHenry, Illinois.
Officers got a call about possible shots fired and responded to the home around 4:15 p.m. Friday, McHenry police said.
The suspect allegedly told officers he had fired a gun in the air and killed his mother while refusing to exit his home. Police were eventually able to get inside and found no evidence of a murder.
The man was taken to a nearby hospital for treatment, officials said.
There was no further danger to the public, police said.
No further information as police continue to investigate the situation.