GENEVA (Reuters) - Four Burundian lawyers who gave information to the United Nations about alleged torture in their central African country face disbarment as retribution for their testimony, U.N. human rights experts said on Monday.

The U.N. Committee against Torture (CAT) urged the Burundian government to provide "urgent reassurances" that no lawyer or activist would be punished for taking part in a special session of the panel in Geneva last month.

The committee of 10 independent experts examined Burundi's record, voicing concern at allegations of killings and torture of opposition figures by the ruling CNDD-FDD party's youth wing Imbonerakure.

The four lawyers - Armel Niyongere, Lambert Nigarura, Dieudonné Bashirahishize and Vital Nshimirimana - contributed to a report by Burundian NGOs for the July 28-28 review, a panel statement said. Three of the men attended the Geneva session.

"On 29 July, a Burundian prosecutor asked the president of the Bujumbura Bar Council to strike the lawyers off, alleging that they had committed several offences, including involvement in an insurrectionist movement and an attempted coup," it said.

CAT wrote the Burundian government noting that the prosecutor had sought sanctions against the lawyers, rather than an inquiry to establish the facts, “which raises concerns with respect to presumption of innocence”.

A Burundian government delegation expected to take part in the second day of the CAT session then indicated it would stay away in protest at the NGOs' report, the panel said.

In opening remarks to the panel quoted by a U.N. summary, Burundian Justice Minister Aimée Laurentine Kanyana said torture was prohibited in Burundi and perpetrators were tracked down, tried and punished in line with national law.

New York-based group Human Rights Watch said it was clear the Burundian government preferred to "duck tough questions rather than engage with the U.N. on human rights, or take meaningful action to prevent torture".

The U.N. panel asked Burundian authorities to address its concerns by Thursday, a day before its conclusions are issued.

Burundi is mired in a year-long crisis in which more than 450 people have been killed since President Pierre Nkurunziza pursued and won a third term. Opponents said his move violated the constitution and a deal that ended a civil war in 2005.

(Reporting by Stephanie Nebehay; editing by Mark Heinrich)