Human rights groups, rebels and indigenous activists have accused Philippine President Rodrigo Duterte of inciting the military to commit war crimes after he offered a $384 bounty for each communist rebel killed.

Duterte's "incendiary rhetoric" encourages violations of conventions on armed conflicts, Carlos H Conde of Human Rights Watch, said in a statement to Al Jazeera on Thursday.

"Duterte's pronouncements normalise the idea that government security forces can do as they wish to defeat their enemies - including committing summary executions," said Conde.

Last week, Duterte said he would train indigenous people, or lumads, to become paramilitary fighters and pay them 20,000 pesos ($384) for each communist rebel they kill in their communities in the southern island of Mindanao.

"You want money? I'll give you money," he said. "I will make it 20,000 pesos per head."

The controversial comments followed an earlier report quoting Duterte as telling the military to shoot female communist rebels in the genitals, to make them "useless".

Cash for killing

The president made the bounty offer after the recent killings of an indigenous leader and his son, who were known members of a paramilitary force in their community.

The armed communist rebel group, New People's Army, has claimed responsibility for the killing in early February, accusing the two of "land grabbing and extortion".

Jose Maria Sison, the exiled leader of the Communist Party of the Philippines, said Duterte is "acting like the chieftain of a criminal gang" with his order.

In a statement to Al Jazeera, Sison warned Duterte´s solution would result "in massacres and violations of human rights and international humanitarian law".

"The cheapest, most beneficial and best way to solve the nearly 50 years of armed conflict in the Philippines is to engage in peace negotiations," Sison said.

He said the government should address the root causes of the armed conflict and "work out comprehensive agreements on social, economic and political reforms in order to lay the basis for a just and lasting peace".

Instead of promoting measures to ensure those responsible for abuses, including communist rebels, are held accountable in accordance with international law, Duterte is "encouraging his troops to commit war crimes" with his bounty offer, Conde of Human Rights Watch said.

Rachel Chhoa-Howard of Amnesty International also denounced Duterte's latest policy as "both appalling and inhumane".

"By putting a price on human life, President Duterte has again exposed the callousness of his administration's policies," Chhoa-Howard said in a statement to Al Jazeera on Thursday.

"It encourages killing rather than capturing insurgents, in clear violation of the right to life."

'Insult to indigenous people'

Accusations of international law violations have hounded the Philippine leader since he came into office in 2016.

Recently, the International Criminal Court announced it had taken the first step to investigate Duterte for possible crimes against humanity over his drug war, which has killed thousands of people.

Meanwhile, the Alternative Learning Center for Agricultural and Livelihood Development (ALCADEV), one of the largest indigenous groups in the southern Philippines, said killing for money is not part of their culture.

"To even ask us to kill, as if killing is the way to peace in our communities, shows ignorance of our plight and our struggle.

"The underlying principle of our struggle to defend the land of our ancestors can never be bought," an ALCADEV statement posted on social media said.

"We've never asked you to kill anyone; all we've ever asked for is justice."

Chad Booc, who teaches indigenous children in Mindanao, told Al Jazeera the real culprit of violence in indigenous areas in the southern Philippines is the military.

He said the government is targeting indigenous lands, where coal mining operations are being planned.

Booc said the military had been harassing indigenous communities, alienating them, and turning them against the government.

He added that the indigenous community finds the president's offer "insulting" and feels outraged "that the president thinks so lowly of them, that they will be enticed to kill" for money.

Bloody rebellion

Jerome Succor Aba, head of an alliance of Muslim and indigenous groups, said in a statement that his community "survived centuries without much need of cash", by using the resources of their ancestral lands.

The communist rebels said they operate in the area to protect indigenous people from military harassment.

The Duterte administration has been engaged in on-and-off peace negotiations with the rebels since mid-2016.

But following new clashes between government forces and rebels in 2017, Duterte signed a proclamation labelling the communist fighters a "terrorist" group, essentially breaking off the peace process.

The military has also compared the communist rebels to armed Muslim fighters, who have pledged allegiance to the Islamic State of Iraq and the Levant (ISIL, also known as ISIS). But the communists say they are fighting for social justice and equality.

The Communist Party of the Philippines (CPP) launched a rebellion in 1968 that has so far claimed the lives of more than 30,000 people.

Meanwhile, Sison, the communist leader, warned of a "bigger civil war" in the Philippines, if Duterte "succeedds in concentrating powers in his hands as a fascist dictator".

Sison was referring to Duterte's push to change constitution that would pave the way to a federal form of government.

This article was updated to include the statement of Jose Maria Sison, the exiled leader of the Communist Party of the Philippines.