Updated

Congo's government has obtained a five-minute cell phone video that shows the gruesome murders of two United Nations experts who were killed last month while investigating human rights abuses.

In the video shown to journalists on Monday, a group of young men identify themselves as members of the Kamwina Nsapu militia.

American Michael Sharp, Swedish national Zaida Catalan and their interpreter Betu Tshintela went missing March 12 in central Congo and their bodies were found two weeks later. Three others working with the team remain missing.

Congo's government has vowed justice for the victims and arrested two suspects, though one escaped custody.

More than 400 people have been killed and more than 200,000 displaced since government troops killed the militia's leader in August, according to the U.N.