Sri Lanka, Dec. 15 -- Australia vowed stricter gun laws on Monday as it began mourning victims of its worst mass shooting in almost 30 years, in which police accused a father and son of killing 15 people at a Jewish celebration at Sydney's famed Bondi Beach.

The older gunman, aged 50, was killed at the scene, taking the tally of dead to 16, while his 24-year-old son was in a critical condition in hospital, police told a press conference.

Police have not released the suspects' names but national broadcaster ABC and other media have identified them as Sajid Akram and his son Naveed Akram. Two flags of militant group Islamic State were found in the gunmen's vehicle, ABC News reported, without citing a source.

The incident has raised quest...