Colombia's government and its biggest rebel movement say they'll work together to locate thousands of people who vanished during more than 50 years of conflict.

They made the announcement Saturday in Cuba, where representatives of the government and the Revolutionary Armed Forces of Colombia are trying to reach a peace treaty.

The say they'll try to find, locate and identify the missing, as well as return remains to families. They will use information from rebels and security forces, as well as social organizations.

The two sides have said they plan to reach a final peace deal by March.

Some 25,000 people are registered as missing since 1985. An estimated 220,000 have died and 6 million have been driven from their homes.