Several people are dead after a gunman opened fire at a synagogue during a baby-naming ceremony in the US.
A shooter launched an assault at the Tree of Life Synagogue in the Squirrel Hill neighbourhood in Pittsburgh on Saturday.
US media reported eight people were dead and some 12 more hurt, though this has not been stated officially.
Pennsylvania's attorney general has stated the incident occurred during a baby-naming ceremony at the religious building.
Officials have not stated how many people were killed though police at one point said "several" died with indications the death toll might be considerably higher.
Six were wounded, including the four police officers, said Pittsburgh public safety director Wendell Hissrich.
Police responded to the active shooter shortly before 10am US time.
By 11.20am local time one suspect had been taken to custody.
A law enforcement official has identified the suspect in a shooting at a Pittsburgh synagogue as a man named Robert Bowers.
The official, who spoke on condition of anonymity, said Bowers was in his 40s.
A "bearded heavy-set white male" was detained, KDKA television said.
Reports also stated a man shouted "all jews must die" as he entered the building, attributing this detail to police sources.
Police spokesman Chris Togneri said police have no more information at this time.
He explained that they are still trying to clear the building and determine if any more threats exist.
A Tweet from the Pittsburgh Public Safety Department, as the situation unfolded, said: "ALERT: There is an active shooter in the area of WILKINS and Shady. Avoid the area. More info will be released when it is available."
President Donald Trump has Tweeted about the incident and said: "Watching the events unfolding in Pittsburgh, Pennsylvania. Law enforcement on the scene. People in Squirrel Hill area should remain sheltered. Looks like multiple fatalities. Beware of active shooter. God Bless All!"
Footage from the scene shows a heavy police presence in the area.
One person, who works nearby, wrote on Twitter: "There was just a man who opened fire in the synagogue down the street from my job. We’ve seen 15+ police cars drive by."
A nearby university, Carnegie Mellon, is said to have been on "lockdown" in the aftermath.
A tweet from the institution said: "From Carnegie Mellon University Police Department: A police operation is occurring at the corner of Shady & Wilkins Avenue. Please avoid area until further notice."
This page is being updated.
