At least 11 people were killed after a gunman opened fire during a ceremony at a synagogue in the state of Pennsylvania on Saturday, said an official.
The fatal incident occurred at the Tree of Life Congregation Synagogue in Pittsburgh at around 10 a.m. local time (1400GMT), according to reports.
Police have taken the assailant into custody, said Pittsburgh Public Safety Director Wendell Hissrich at a press briefing.
"There were no children. There were additionally six injuries to include four of the police officers. That does not include the suspect," said Hissrich.
Multiple reports said the shooter has been identified as Robert Bowers, 46.
U.S. President Donald Trump told reporters in Indiana that "what happened today is a horrible, horrible thing" after earlier tweeting that the "events in Pittsburgh are far more devastating than originally thought."
"It looks definitely like it's an anti-Semitic crime," he said in Indiana. "That is something you wouldn't believe could still be going on. But it would seem to be an anti-Semitic crime."
The tragedy is being investigated as a hate crime by the FBI.