Belgian paratroopers pulled out of this tense and death-filled city in southern Zaire yesterday, leaving a joint French-Zairian force to defend it against rebels who still have not given up their fight to take or paralyze the important copper mining center.

The 1,700 Belgian soldiers left during a bitter controversy among the French, Belgians and Zairians here over Brussels' decision to evacuate all its nationals. This is blamed here for having triggered a panicky exodus by the entire European population that has effectively left the 800 French Foreign Legionnaires and a reinforced Zairian battalion providing security for a ghost town.

The departure of the Belgians, furthermore, has put the burden on France alone for the future defense of Kolwezi, although Belgian Premier Leo Tindemans announced yesterday that Belgium will keep a battalion of paratroopers at Kamina, 150 miles north of here.

There is serious concern among Zairians and foreigners here that the rebels will again overrun the city when the tough French Legionnaires leave. France has no mutal defense pact with Zaire and has described the purpose of sending its Legionnaires as strictly humanitarian and limited to the rescue of the White hostages.

Contrary to the earlier reports, rebel commandos continue to operate in and all around Kolwezi and Sunday night there was heavy shooting even in the vicinty of the French Foreign Legion's headquarters in the pillaged Hotel Impala in the center of the city.

At least four arms caches have been uncovered by the Legionnaires in house-to-house searching in the city's black quarters and French military sources believe some of the rebels are still holding out in isolated spots inside the European sections of the town. It appears others are infiltrating back into town at night or passing themselves off as civilians among the city's blacks.

Legion Commander Col. Philip Eurlin told Western correspondents yesterday that the rebels had lost 300 men in battle with his troops, who were dropped on Kolwezi Friday to break a six-day occupation of the town. The Legion's casualties so far in the rescue mission to evacuate more than 2,000 white hostages have been two dead and nine injured, he said.

The battle-hardened colonel called the carnage of whites here "indescribible and horrible" and said he had never, in a lifetime of fighting around the world, seen anything like it.

The stinks and sights of death permeate this once-prosperous city of small, neatly kept villas and bungalows surrounded by trim hedges and flowering bougainvillea shrubs. Mutilated and stinking black and white bodies are still scattered everywhere in the downtown and European areas where most of the fighting between rebel and Zairian and French forces seems to have taken place.

A new site with the bodies of 17 blacks and one European teenager has just been discovered above a pond near the center of town. This is the known mass execution of blacks, although other are feared.No one has yet done anything but count the blood-and-fly-covered figures who were apparently told to run and then were shot.

The death toll will probably never be accurately recorded but local estimates put it close to 500 for the blacks, including the rebels, and between 120 and 150 among the whites. Most of the white victims were killed at three or four sites. One incident, involving 20 men, was committed by the Zairian Army and not the invading rebels, according to accounts by two survivors.

The body of an American missionary, identified only as Kenneth, was uncovered over the weekend bringing the number of known American deaths here to four.

The extent of the terror for some of the Europeans was brought home to visiting correspondents by an incident Sunday.Paratroopers found 13 Belgians still hiding behind locked doors in their homes. They refused to come out until they heard the Belgian paratroopers speak in Flemish.

How this city can ever be revived or the copper mines made to function again remained unanswered at this point. Most of the 2,200 Europeans who once lived here have gone and one of the half dozen still remaining behind yesterday, said it was unlikely he or others would return soon. "Hw can we go on living here," said Jean Someville, 65, a businessman in Kolwezi for 28 years. "There is no food, no water, no electricity, no nothing."

He departed with four other Belgians yesterday, leaving only two or three European quarters of the city.

Nobody has begun to clean up the streets or bury bodies and blacks were picking over store contents or moving through the streets with their belongings apparently returning to their homes after having fled into hiding during the rebel siege.

The city's main street is strewn with the unwanted remains of goods from shops and the spirit that apparantly prevailed during the six-day occupation was aptly summed up in the "self service" sign on a general food store.

Without expatriates, there is no way the huge open pit and underground copper mines can be made to function. In addition some machinery has been sabotaged and water is filling the mines because a power failure has stopped the pumps.

Estimates of the time it will take to get the mines here going again vary from six months to two years depending on how successful the big Belgian-Zairian mining concern Gecamines is in convincing Europeans to come back.

With Kolwezi the biggest mining center and copper by far the most important source of both government revenue and foreign exchange, the battle for the city has all the makings for a major Zairian economic disaster.

The present desperate plight of the city is bound to fuel the feud between Paris, Brussels and Kinshasa over how the whole rescue operation was handled. The Belgians apparently wanted to negotiate with the rebels and were taken somewhat by surprise when the French, acting on their won, rushed the Legionnaires into action before the Belgian paratroopers were ready.

The tension between Paris and Brussels was clearly reflected here in Kolwezi where French and Belgian paratroopers barely cooperated with each other and the Belgian refugees complained about being rescued by French Foreign Legionnaires.

The Legionnaires did all the fighting to oust the rebels from the town while the Belgians provided security for an airfield already retaken by Zairian troops and took charge of collecting Europeans from their homes and bringing them to the planes.

The Foreign Legion commander Col. Erulin, hotly defended the behavior of his men, who have been accused by some Belgian refugees of opening fire and killing at least one European at a roadblock on the way to the airport.

My mission was to rescue, not kill, them and all my men were given strict instructions on how to behave toward civilians, black or white," he said.

He cited the successful last-minute rescue by the Legionnaires of 31 hostages being held at a college, just as they were being lined up to be executed. One European died before the paratroopers, who landed in a nearby deal with the rebels but the others were saved.

Various sources said however, that a Yugoslav was killed by the Legionnaires at the roadblock. His body could still be seen lying there yesterday. He was reportedly speeding toward the checkpoint just at sundown and failed to slow down when the soldiers signaled him to stop.

Wire services reported these developments:

Jonas Savimbi, leader of a movement opposed to Marxist President Agostinho Neto's government in Angola, was reportedly captured by rebels who invaded Zaire a week ago, a Belgian refugee claimed yesterday in Brussels.

The refugee, a technician for a mining firm he declined to identify, said he held the information from reliable Zaire sources I know in the area."

He said he was unable to provide details but that his informers indicated Savimbi, leader of UNITA, was taken prisoner shortly after the attack. The UNITA sources in Brusels said it was "very possible" that Savimbi was in the area at the time of the rebel attack.

Meanwhile, Tass, the official Soviet news agency said 200 "thugs" attacked its embassy in Kinshasa on Friday and caused serious damage in an attempt to distract attention from the French-Belgian operation in southern Zaire. Working with the connivance of local police, the attackers wreaked havoc, threatened the lives of the embassy staff and their families, Tass said.