At least four people were shot when a gunman opened fire just after 10 a.m. CDT Sunday at the Sikh Temple in Oak Creek, Wisconsin, about 12 miles south of Milwaukee, with both injured and uninjured people being removed from the building, The Milwaukee Journal Sentinel reported.
Among the injured is the temple's president, who was taken to the hospital.
At least one gunman opened fire during morning services at the temple, and remained on the loose inside the temple, possibly holding hostages, according to witnesses, Reuters reported.
Police, ambulances and the fire department were on the scene at the Sikh Temple of Wisconsin, located about 20 minutes south of Milwaukee.
The dispatcher for Oak Creek Fire Department said first reports of the shooting came in about 10:30 a.m. local time (11.30 a.m. EDT).
"We do have a shooting," she said. "Our whole department is out there, and others as well." She did not have details on any possible victims.
Police officials declined to comment.
It was unclear how many people may have been wounded in the shooting. But two witnesses said the shooter or shooters were still inside the building.
Carolyn Bellin, spokeswoman for Froedhart & The Medical College of Wisconsin in Milwaukee, told CNN two men had been brought in and one was undergoing surgery.