Fleeing Rwandan Troops Shoot and Loot : Africa: Some units escape into Zaire behind civilians. Rebels air an appeal for surrender.

Edgy Rwandan government troops, intoxicated on beer and marijuana, systematically looted this onetime resort town on the border with Zaire on Saturday and randomly fired revolvers and automatic weapons to discourage any effort to stop them.

On Saturday morning, a French colonel commanding two dozen troops sent in from nearby Goma to evacuate 168 Hutu orphans told his men, “Watch out, because the Rwandan soldiers are hashed to the eyeballs.”

As the troops gutted government offices, stores and private homes, cargo aircraft roared overhead, bringing in the first emergency relief supplies for the hundreds of thousands of Hutu refugees who have crossed into Zaire for fear of reprisal by predominantly Tutsi Rwandan Patriotic Front rebels.

The rebels have taken over most of the country since Hutu majority extremists began massacring Tutsis and moderate Hutus after an unexplained plane crash killed Rwanda’s Hutu president April 6. Up to half a million Rwandans have died in the upheaval, according to U.N. estimates, and even more have fled the country.

Some officials in Goma, Gisenyi’s sister city across the Zaire border, estimated that more than 500,000 refugees have crossed over since Thursday, while others have given lower figures.

Long after nightfall, the sound of automatic arms and explosions here was audible miles away in Goma.

And still later, some government troops retreated with their weapons over the border into Zaire as rebel forces said they had reached the outskirts of Gisenyi, Reuters news service reported.

Reporters close to the border saw at least 20 trucks loaded with Rwandan troops and four anti-aircraft guns drive through Goma, the agency added.

Reuters also reported that the Tutsi-led front, in a radio broadcast, called on government troops to surrender.

“We call upon all those soldiers . . . and citizens who have fled to Gisenyi or other areas, to give themselves up to the RPF forces and return to their homes, instead of continuing to listen to those who have cheated them and have launched a war which they cannot fight,” said rebel Radio Rwanda, monitored by the British Broadcasting Corp.

Maj. Gen. Augustin Bizimungu, the Rwandan army’s chief of staff, summed up the situation as “catastrophic” as he emerged from a meeting at Goma’s airport with Maj. Gen. Romeo Dallaire, commander of the U.N. force trying to end more than three months of fighting.

Although the International Committee of the Red Cross estimated that 800,000 Hutus would cross into Zaire, disaster relief specialists began to express cautious optimism about Africa’s worst refugee crisis.

Lionel A. Rosenblatt, president of Washington-based Refugees International, said, “I think we can still avert a disaster, despite a slower start than we would have liked.” Two flights carrying a total of 60 tons of corn arrived in Goma from neighboring Uganda, the first contribution from the United Nations’ refugee relief agency.

“We are doing our best to cope with a lack of adequate preparedness,” agency spokesman Panos Moumtzis told reporters. He acknowledged the shipments represented “just a drop in the ocean,” but said air deliveries by Monday should amount to 240 tons a day, with the bulk of the 600 tons needed daily coming by road.

The Red Cross flew in 34 tons of plastic sheeting for shelters but expressed concern about fighting among refugees for equitable distribution.