Burundian President Pierre Nkurunziza on Wednesday promised that those responsible for recent political violence will soon face justice.

"I want to tell you that those responsible for the violence that we see today will soon answer for their actions," Nkurunziza said in a speech broadcast in Kirundi, the country's national language.

"We are going to put in place in the coming months a commission charged with investigating the violence that took place during the elections," he said, referring to Burundi's 2010 poll, won by the incumbent.

The president said "no one should think that they can escape justice or that they can seek refuge in Tanzania or the Democratic Republic of Congo and escape us."

"We will follow you and bring you back with your arms tied behind your back," Nkurunziza said, clearly referring to Agathon Rwasa, leader of the National Liberation Front, a former rebel group that agreed to disarm in 2009.

Rwasa went into hiding in July 2010, and has since been based in the eastern DRC.

For the second time in recent days, Nkurunziza, who is a member of the Hutu ethnic group, made reference to Burundi's history of tribal tensions, a rarity from the president.

"The defence and security forces that used to be in the hand of only one ethnic group are today composed of all ethnicities," he said, referring to conditions under the previous regime, led by Tutsis.

On May 15, Nkurunziza for the first time mentioned the "ostracism" that the Hutu majority -- who make up 85 percent of the country's 8.5 million people -- felt under the previous regime.

The tiny central African country is still recovering five years after the end of the civil war that started in 1993 and claimed some 300,000 lives.