At least one gunman opened fire in a Sikh temple near Milwaukee on Sunday, killing at least six and injuring several others before being shot himself, the police said. The gunman is also believed to have died.


The shootings occurred about 10:30 a.m. at the Sikh Temple of Wisconsin in the town of Oak Creek, just south of Milwaukee, officials said.


The authorities described the scene at the temple as chaotic as they attended to the victims and tried to sort out what had happened. The police said they were still uncertain whether there were other gunmen at the temple.


Bradley Wentlandt, the chief of police in nearby Greenfield, told journalists on the scene that four bodies had been found inside the temple and three were found outside, including that of the suspect. He said a veteran police officer who arrived on the scene exchanged fire with the gunman.


“That officer was shot multiple times,” Mr. Wentlandt said. “The shooter was put down.” He said the injured officer was taken to the hospital and it was unclear whether he would survive. The suspect, who was not immediately identified, was “assumed deceased,” he said.


At least three men, all with gunshot wounds, have been admitted to Froedtert Hospital, the Milwaukee region’s main trauma center, said Nalissa Wienke, a spokeswoman for the hospital. One victim was shot in the head and extremities and another in the abdomen. The third was undergoing evaluation.


The Milwaukee Journal Sentinel reported that victims were being removed from the temple’s prayer room and that a SWAT team was sweeping the building. The newspaper reported that the temple’s president, Satwant Kaleka, was among those shot.


There were conflicting reports about whether another gunman had taken hostages inside the temple. Local news agencies, citing text messages from people inside have reported that two or more gunmen could have been involved.


The shooting comes just over two weeks after a gunman killed 12 people and wounded nearly 60 in a mass shooting at a movie theater in Aurora, Colo.


In response to the shooting, the police in New York said that security was being increased at Sikh temples in the city. “There is no known threat against Sikh temples in New York City, however, the coverage is being put in place out of an abundance of caution,” the New York police said in a statement.