Philippines President Rodrigo Duterte has threatened to eat the internal organs of Abu Sayyaf Islamists for the third time. The firebrand leader said he would not hesitate to devour terrorists' livers if they are seasoned enough with salt and vinegar.

On two previous occasions, Duterte – who is known for his notorious drug war in the Philippines and his foul language – had warned that he would be happy to eat the bodies of insurgents fighting against the government.

This time, the Filipino leader was speaking after the beheading of two Vietnamese men by Abu Sayyaf, the armed Islamist group of the southern Philippines known for its kidnappings and extortion.

Decapitated bodies of the Vietnamese sailors, who remained Abu Sayyaf hostages since June 2016, were found on Tuesday, 4 July by local villagers.

"I will eat your [Abu Sayyaf militants'] liver if you want. I will just add salt and vinegar, I will eat it in front of you," Duterte told a gathering on Wednesday, 5 July. "I eat everything. I am not picky. I eat even what cannot be swallowed."

He was visibly furious about the brutality of the killings of the Vietnamese. While holding a phone showing the pictures of the Vietnamese victims, Duterte said: "You want to be enslaved by these? Son of a b***h. Let's just circumcise ourselves again.

"What are you really trying to prove with these actions? You take the name of Allah in vain? You use the name of God to kill people that way."

Abu Sayyaf, which has pledged allegiance to the Islamic State (Isis), currently holds 22 hostages which includes 16 foreigners.

This is not the first time Duterte has used such language against anyone who opposes him or his policies. He chooses particularly harsh rhetoric against extremists and drug-peddlers.

Philippines Marawi Isis Islamic State
Philippine President Rodrigo Duterte salutes the honour guards as he arrives at Manila international airport upon returning from a visit to Russia Noel Celis/AFP