At least two gunmen opened fire on a Jewish holiday celebration Sunday on a beach in Sydney, Australia, killing at least 11 revelers and injuring 29 in what authorities immediately declared a terror attack.

One of the gunman was killed at the scene by police, and the other was wounded as citizens intervened to stop the attack. 

The massacre at the popular Bondi Beach came amid a wave of antisemitic attacks that have rocked Australia in recent months.

"This attack was designed to target Sydney’s Jewish community,” Premier Chris Minns said.

Australian Prime Minister Anthony Albanese decried the "act of evil, antisemitism, terrorism that has struck the heart of our nation.” 

Hundreds had gathered for the event called "Chanukah by the Sea" marking the start of the eight-day Hanukkah festival. 

The New South Wales Police Force said 12 people were killed in the shooting, including one of the two suspected gunmen, and that authorities are open to the possibility a third gunman had escaped.