Naveed Akram previously known to security agencies, prime minister says. His gun-owning father, Sajid, was shot dead by police at the scene

The alleged gunmen behind the Bondi beach attack are a father-son duo suspected of using legally obtained firearms to commit the massacre, according to police.

Naveed Akram, 24, was arrested at the scene and taken to a Sydney hospital with critical injuries. His 50-year-old father, who the Sydney Morning Herald first reported to be Sajid Akram, was shot dead by police.

The pair allegedly killed 15 people, with dozens more injured in the shootings, which took place on Sunday during a gathering to celebrate the first night of Hanukah.

The son was known to New South Wales police and security agencies, while his father had a firearms licence with six weapons registered to him. All six firearms have been recovered, police said.