Explosions ripped through a densely populated Kinshasa suburb today after soldiers opened fire on a helicopter that was buzzing overhead, witnesses said. Several people were killed and many more were wounded.

Early reports were contradictory, with some witnesses saying a rebel helicopter had been shot down and crashed in an eastern suburb near the city's airport. Others said it was actually a government helicopter, and it did not crash, but stray rebel rockets fired at the aircraft had exploded on the ground.Congo's government is trying to survive a rebel assault by ethnic Tutsi fighters from eastern Congo and Rwanda and disenchanted members of President Laurent Kabila's army.

The rebels had slipped into parts of Kinshasa, the capital, in recent days and launched an offensive to take the airport.

But on Thursday, the government and allied troops from Angola, Zimbabwe and Namibia were firmly in control of the airport. More than 1,000 prisoners had been captured in and around the capital, the government said.

Today, thousands of people were fleeing the eastern Kingasani suburb near the airport, where heavy fighting was reported.

"The body of the helicopter was still burning on the ground," said Bernard Makenga, a local Congolese journalist who said he witnessed the crash. "People were crying and screaming."

But other witnesses claimed the helicopter escaped the ground fire, with at least one rocket slamming down on a crowded area.

A government commander described the helicopter as a green military aircraft and claimed it was flown by rebel pilots.

It was not clear how many people were killed, though Makenga said he saw many bodies scattered about.

Earlier today, the government broadcast an appeal on state radio asking rebel soldiers who had defected from Kabila's army to lay down their arms.

Joseph Kabila, the president's son and new military chief, also called on the public not to attack Congolese soldiers trying to surrender but said nothing about ethnic Tutsi fighters.

Government troops on Thursday ran amok in parts of Kinshasa, taking revenge on suspected rebel fighters. The discarded bodies of 18 men, some charred and disfigured, were spotted on city streets and back alleys.

One captive, wailing for mercy, was hurled off the side of a bridge and then shot to death.

The killings infuriated rebel leaders, who warned they would "severely punish those who think like Kabila and are guilty of bloody crimes of lynching people in Kinshasa."

The insurgents had scored repeated military successes early in the rebellion that began more than three weeks ago.

But the deployment of the Angolan, Zimbabwean and Namibian troops has apparently turned the tide in the southwest.

Zimbabwe's official news agency today reported that about half the 8,000-strong rebel force on Congo's southwestern front either had been captured or killed.

Rwanda and Uganda - which helped Kabila to oust longtime Zairian dictator Mobutu Sese Seko in May of last year - turned on him because of his inability to stem cross-border attacks by militants based in eastern Congo.