Several schools across Sydney were evacuated on Friday morning following bomb threats, Australian police said.

Schools in Woolooware, Ulladulla, Richmond, Penrith and Mona Vale received the threats between 10.50 am and 11 am local time, New South Wales police said.

Students and staff of Woolooware High School have been evacuated to nearby Shark Park, Seven News said. Evacuations are taking place at Penrith High School.

Students were not in harm and there was no confirmation that the bomb threat was genuine, Sydney Morning Herald said.

"The cops just blocked both side of the road and were getting all the children over to Sharkies leagues club immediately," an eyewitness told Seven News.

"Several police operations are underway at NSW schools. The first call about in about 11am. Police are aware of numerous threats made to schools in the Metropolitan and Southern Regions. Investigations are continuing, and police are liaising with the Department of Education," an NSW police spokesman said.