BENI, Democratic Republic of Congo, March 3 (Reuters) - An U.N.-backed offensive by Democratic Republic of Congo troops has destroyed the bases of an Ugandan Islamist group in the country's east and should crush the rebels in the next few days, an army spokesman said on Monday.
The Congolese army has been fighting the ADF-NALU militia since December following rebel attacks against civilians in the eastern province of North Kivu.
"We're progressing well in the operations against ADF-NALU. In a few days we will finish with them," army spokesman Colonel Olivier Hamuli said in the town of Beni in North Kivu.
"We have destroyed all of the bases which were supporting their supply lines. They're now badly positioned and in a few days we will overcome them."
The army's advance followed stepped up support from U.N. forces, with U.N. attack helicopters bombarding ADF-NALU positions on Saturday.
ADF-NALU is an alliance of groups opposed to the Ugandan government that has operated from bases in eastern Congo since being forced out of Uganda in the mid-2000s.
It has been blamed for a spate of kidnappings and attacks over the last year, culminating in a Christmas Day assault near Beni that killed about 40 civilians. It is believed to number up to 1,400 fighters.
Martin Kobler, the head of the U.N. mission in Congo (MONUSCO), called on the rebels to surrender.
"I urge the last fighters to put down their weapons immediately and surrender to MONUSCO camps," he said in a statement.
If ADF-NALU were to be defeated, it would be the second major victory for Congo's army in less than a year after it routed the M23 rebel group in November.
At the height of its powers in late 2012, M23 seized Goma, the capital of North Kivu province, and posed the most serious threat to President Joseph Kabila's 13 years in power.
That prompted the formation of an Intervention Brigade of U.N. troops with a mandate to hunt down and neutralise armed groups in Congo's lawless east, home to dozens of rebel factions and militias. (Reporting By Chrispin Mvano in Beni and Peter Jones in Kinshasa; Editing by Angus MacSwan)