Rodrigo Duterte is shown in a YouTube video telling a crowd of laughing supporters at a campaign rally: "They raped all of the women. ... There was this Australian lay minister ... when they took them out ... I saw her face and I thought, 'Son of a bitch, what a pity ... they raped her; they all lined up.' I was mad she was raped but she was so beautiful. I thought the mayor should have been first."

The missionary, who was ministering in a prison in Davao in the southern Philippines in 1989, was raped and killed during a riot by inmates, when Duterte was the city mayor.

Duterte - who promises to go ahead with mass killings of suspected criminals if elected on May 9 - currently leads the polls.

Condemnation

His election rivals, women's groups and social media commentators quickly attacked the remarks.

"The comments show his lack of fitness for the presidency and his utter lack of respect for women," President Benigno Aquino's spokesman Herminio Coloma said.

Aquino, who cannot seek a second term under the constitution, supports his former interior secretary Mar Roxas in the election.

Another presidential candidate, Vice President Jejomar Binay, called Duterte's remarks "simply revolting."

"You are a crazy maniac who doesn't respect women and doesn't deserve to be president," Binay said in a statement.

Women's group Gabriela attacked Duterte's remarks, saying rape or any other form of sexual abuse was not a joke "nor something to be trivialized in a joke," especially by someone seeking the presidency.

The worse, the better

Many Filipinos have celebrated Duterte's vulgarity-laced speeches, his boasts of sexual conquests and his promised war on crime. He called Pope Francis a "son of a whore" in a speech in November, but was quickly forgiven.

"We won't apologize for he has done nothing wrong, it was a clear joke for God's sake," one supporter said on Twitter.

A lawyer by training, Duterte has served the most years of any mayor in the Philippines, governing Davao City for a total of seven three-year terms. In between, he has either been vice mayor or a congressional representative of the city.

He has four children by two women, and claims to have three girlfriends.

As mayor of Davao City, he has been credited for transforming the metropolis of more than 1.4 million people into a commercial hub in the southern region of Mindanao.

Duterte has been linked to a vigilante group called the Davao Death Squad, which has been blamed for hundreds of murders, though he has never been formally charged with being behind the squad.

jbh/bk (AFP, dpa)