Philippines presidential candidate Rodrigo Duterte has come under fire for joking about a murdered Australian victim.

The incident, which was caught on film, showed Duterte and his supporters joking about a missionary who was assaulted, raped and murdered by prisoners in 1989. At the time Duterte was mayor of the town. In the clip, someone jokes that Duterte "should have been first."

Duterte regularly brags about his sexual escapades and makes speeches that are criticized as irreverent.