By Elias Biryabarema
KAMPALA (Reuters) - Uganda is holding the military commander of Congo's defeated M23 rebel movement after he surrendered, a Ugandan officer said on Thursday, as relief at the end of his rebellion was tempered by concerns about other armed groups.
Sultani Makenga's whereabouts had been unclear since Tuesday's declaration by the M23 that it was ending its 20-month insurgency in eastern Democratic Republic of Congo, worrying some that he could be hiding with plans to regroup.
His surrender will be seen as a major achievement for the Congolese army, with the backing of a U.N. force, as it strives to restore calm in a region racked by war for two decades.
But analysts have warned against too much optimism for a sustained peace in the mineral-rich east of the vast nation, where a plethora of other groups still operate.
"I can confirm to you he (Makenga) is with us," the senior Ugandan officer, who asked not to be named, told Reuters.
"He surrendered to us yesterday (Wednesday) and we're holding him somewhere and some other commanders of his," he said, adding the group of rebels would be held at an undisclosed location until a peace agreement was signed.
The Congolese government had no immediate comment.
The M23 group declared an end to its military campaign and said it would seek political talks after Congolese troops routed them from their hide-outs with U.N. support.
Captain Ronald Kakurungu, a spokesman for Uganda's army, said 1,500 M23 rebels had surrendered and disarmed.
That figure is higher than most previous estimates of the strength of the M23, which experts had generally believed to have dwindled in recent months to a few hundred.
Bertrand Bisimwa, M23's political leader, did not confirm any numbers but said in a statement fighters had crossed into Uganda as they felt unsafe joining a disarmament process run by the same U.N. and government forces they had fought against.
While recognizing the successes of the joint U.N.-Congo force, analysts said the defeat of the M23 did not mean that a return of order in Congo's east was assured.
"Just because you think you've beaten back the M23 rabble rousers in the east, do you really think it can become a stable country? I don't think so," said Martyn Davies, chief executive of the Johannesburg-based Frontier Advisory.
"This time next year, you'll be looking at an 'M24'," he said.
FDLR ON THE RADAR
U.N. spokesman Farhan Haq said that the U.N. mission in Congo had warned other armed groups that they would face resistance if they sought to take areas abandoned by M23.
The M23, which U.N. experts and Western powers had said was backed by Rwanda, initially launched its campaign when it said a 2009 peace deal with a previous Tutsi-led group of rebel soldiers had not been honored by the Congolese government.
Rwanda has been involved in several conflicts in Congo over the years but denied backing the M23.
Briefing the 15-member Security Council on Congo, French U.N. Ambassador Gerard Araud said Rwandan Hutu FDLR rebels were likely to be among the next targets in Congo.
Some FDLR fighters were part of the militia that took part in Rwanda's 1994 genocide and subsequently fled into Congo's east. Their presence there and previous collaboration with Congolese forces have been used as justification by Rwanda for interventions in its much larger but weaker neighbor.
Millions of people have died from violence, disease and hunger since the 1990s as dozens of rebel groups have fought for control of eastern Congo's deposits of gold, diamonds, copper, cobalt and uranium.
Last month, Washington said it would block U.S. military aid to Rwanda because of its "support for the M23, a rebel group which continues to actively recruit and abduct children" and posed a threat to the stability of Congo.
A senior U.S. official said on Wednesday that Washington would consider resuming military aid to Rwanda if it found Rwandan support for M23 had ended.
(Additional reporting by Pete Jones in Kinshasa, Pascal Fletcher in Cape Town and Michelle Nichols in New York; Writing by Edmund Blair and David Lewis; Editing by Robin Pomeroy)