Authorities responded to a shooting Saturday morning near the Tree of Life synagogue in Pittsburgh, according to Allegheny County Sheriff's Deputy Kevin Kraus.

Three police officers have been shot and there are fatalities, officials said at an impromptu press conference. The shooter has surrendered, they said.

“There are fatalities,” said Allegheny County Executive Rich Fitzgerald, but officials have not provided more details.

Pittsburgh police Cmdr. Jason Lando there were “multiple casualties.” Officers were dispatched to the scene after receiving reports of active gunfire at the synagogue, he said.

“It is imperative that the neighbours in the community surrounding the Tree of Life synagogue stay in their houses and shelter in place,” Lando said. “Do not come out of your home right now. It is not safe.”

The Tree of Life synagogue is a conservative Jewish congregation, according to its website. It's in Squirrel Hill, a historic, Jewish neighbourhood.

The synagogue has a Shabbat service at 9:45 a.m. Saturdays, the website said.
President Donald Trump tweeted he was aware of the situation in Pittsburgh and that law enforcement was on the scene.

“People in Squirrel Hill area should remain sheltered,” Trump said. “Looks like multiple fatalities. Beware of active shooter. God Bless All!”

Pennsylvania Gov. Tom Wolf said on Twitter that it was a “serious situation,” and the state police were helping local first responders.

Carnegie Mellon University issued a shelter in place advisory for its campus, which is near the synagogue.