A lawyer representing families of victims of killings and torture in Burundi has said he is hopeful the International Criminal Court (ICC) may launch an official investigation into alleged crimes against humanity committed in the small East African country.

The bloody crisis that has killed up to 900 people, pits supporters of President Pierre Nkurunziza against those who say that his re-election in July 2015 for a third term violated the nation's constitution. After a failed coup, the government intensified its crackdown and most of those arrested or disappeared today are young men and women accused of participating in or supporting opposition groups, including armed groups whose attacks have also left dozens dead.

Bernard Maingain, one of the three lawyers representing the families of victims of alleged extra-judicial executions, exclusively told IBTimes UK he has met with the Office of the ICC Prosecutor, Fatou B. Bensouda, in The Hague.

"We met with the Office of the Prosecutor. We are confident."

In April 2015, the ICC launched a preliminary inquiry into alleged crimes committed in the country, but is yet to open an official investigation.

The lawyer is not allowed to disclose the content of his communication with the Office of the Prosecutor, but Maingain revealed he met "people who are extremely attentive to civil parties' situation who are very aware of the significance of the fact we have hundreds of warrants in a case of crimes against humanity."

Burundi's civil society lawyer added: "The big novelty is that we arrive already with all these warrants. Usually, complaints are introduced, but mandates confirm families' will to collaborate with the ICC. They have already extensively collaborated with different United Nations observers. The ICC knows we have a capacity to mobilise families to advance the truth-seeking process through people's testimonies."

Bernard Maingain, Burundi putschists' lawyer
Bernard Maingain is one of the three lawyers representing the families of victims of alleged extra-judicial executions and torture in Burundi MEHDI FEDOUACH/AFP/Getty Images

Maingain confirmed his team currently has some 200 warrants, as more families are willing to come forward despite their fears. "We continue to receive a lot of warrants. People really want this case to progress." In March last year, Burundi's Attorney General warned families of victims not to submit evidence to the ICC.

"We have explained them that once the investigation is launched, we can put in place protection measures at the benefit of the populations. People understand that well now, so the bond of trust is established."

There are currently no protective measures in place but information give by families of victims will not necessarily appear in the official record. "That information goes straight to the Prosecutor, so confidentiality is ensured."

On 18 February, the families of victims' team of lawyers sent supporting documentation, including photos of people assassinated, never-seen-before photos of torture, original video footage and written testimonies.

As part of the correspondence, the team also sent numerous screen-grabs of websites appearing to show "hate speeches and incitement of ethnic hatred" – charges that are prosecuted by the ICC.

His comments come after the European Parliament on 19 January this year voted a resolution demanding the opening of international investigations in serious crimes committed in the Great Lakes nation.

"The Parliament passing a resolution is a significant effort. It's the first time it's happened," Maingain said.

Barred from the Bujumbura Bar, lawyer Armel Niyongere, who also represents families of victims in the case, was last week accepted as part of the Brussels Bar. While this does not authorise the Burundian lawyer to plead in front of Belgian courts, the move could enable Niyongere to pursue his work with the ICC.