There is no evidence indicating that the two suspects involved in the Bondi Beach attack received any form of military training while in the Philippines, the Philippines' National Security Adviser said on Wednesday.

In a statement, Eduardo Año said that a mere visit to the country does not substantiate allegations of terrorist training, and the duration of their stay would not have permitted any meaningful or structured training.

The alleged father-and-son gunmen opened fire on a Hanukkah celebration at Sydney's Bondi Beach on Sunday, killing 15 in an attack that shocked Australia and heightened fears of antisemitism and violent extremism.

Año said the government was investigating the two men's travel from November 1 to 28 and coordinating with Australian authorities to determine the purpose of the visit, dismissing media reports portraying the southern Philippines as a hotspot for violent extremism as "outdated" and "misleading."

Immigration records show the pair landed in Manila and traveled to Davao City in Mindanao, a region long-plagued by Islamist militancy, before the attack that Australian police say appeared to have been inspired by Islamic State.

Since the 2017 Marawi siege, a five-month battle in which the Islamic State-inspired Maute group seized the southern city and fought government forces, Philippine troops have significantly degraded ISIS-affiliated groups, Año said.

"The remnants of these groups have been fragmented, deprived of leadership, and operationally degraded," he added.