Federal prosecutors have charged a man with 29 counts of violence and firearms offences.
Authorities said he opened fire at the Tree of Life synagogue in Pittsburgh, killing 11 people.
A law enforcement official told CNN the suspect was identified as 46-year-old Robert Bowers.
Mr Bowers is believed to have made anti-Semitic statements during the shooting.
President Donald Trump said “a lot of people” had been killed and injured in a “wicked act of mass murder”.
More to follow…