At least six people have been killed after a gunman opened fire at a Sikh temple near Milwaukee, authorities said.
The suspected gunman was later killed in exchange of gunfire with police.
Police were called to the Sikh Temple of Wisconsin in the suburb of Oak Creek on Sunday morning, when witnesses said several dozen people were gathering for a service.
Greenfield Police Chief Bradley Wentlandt said the first officer to arrive encountered a man police believe was the gunman. The two exchanged gunfire, and the suspect was killed, he said.
Mr Wentlandt said police do not believe a second gunman was involved. He said tactical units went through the temple. They found four people dead inside and three outside the building, including the suspected gunman, he said.
It's unclear how many others were wounded. Mr Wentlandt said he had been told the officer who exchanged gunfire with the suspect and another person had been taken to hospital. He said the officer was shot a number of times and is undergoing surgery.
The spokeswoman for the area trauma centre said three victims were being treated there, including one undergoing surgery.
Sukhwindar Nagr, of Racine, said he called his brother-in-law's phone and a priest at the temple answered and told him that his brother-in-law had been shot, along with three priests. The priest also said women and children were hiding in closets in the temple, Nagr said.
Sikh rights groups have reported a rise in bias attacks since the September 11 2001 terrorist attacks. The Washington-based Sikh Coalition has reported more than 700 incidents in the US since then, which advocates blame on anti-Islamic sentiment. Sikhs do not practice the same religion as Muslims, but their long beards and turbans often cause them to be mistaken for Muslims, advocates say.
Sikhism is a monotheistic faith that was founded in South Asia more than 500 years ago. It has roughly 27 million followers worldwide. Observant Sikhs do not cut their hair; male followers often cover their heads with turbans - which are considered sacred - and refrain from shaving their beards.