Rebels want a restructuring of the Tutsi-dominated army

The Forces for the Defence of Democracy (FDD), the largest Hutu rebel group in the country, had agreed last Sunday to release the MPs.

The agreement came as rebels and government representatives met at a regional summit in Tanzania aimed at strengthening efforts to end a decade-old civil war.

A fourth MP who had been seized with the others was released earlier this month.

The politicians, who were held along with their driver, are members of the Front for Democracy in Burundi (Frodebu) - the main political party of the Hutu ethnic group in the central African country.

This is warning towards Frodebu to put an end to its bad propaganda against the FDD FDD Secretary General Hussein Rajabu

The rebels signed a ceasefire with Burundi's transitional government in December, but both sides have accused each other of violating the agreement and fighting has continued throughout the country.

The FDD's Secretary General, Hussein Rajabu, described the kidnapping last month as a warning.

"They are safe, but this is warning towards Frodebu to put an end to its bad propaganda against the FDD," he told Reuters news agency.

"For some time they have wanted to discredit our image internationally by saying our movement is against peace."

Civil war

An estimated 300,000 people have died in the nine-year conflict between the Tutsi-dominated army and armed Hutu groups.

Two years ago, Hutu and Tutsi political parties signed a power-sharing accord designed to end the war.

The three-year transitional government entered its second and final phase on 1 May when Domitien Ndayizeye, a Hutu and senior member of Frodebu, took over the presidency from Pierre Buyoya, a member of the Tutsi minority.