SARAJEVO, Bosnia-Herzegovina (AP) _ The triumphant Serb commander strode among Srebrenica's captured population Wednesday, patting one boy on the head, as his rebels herded terrified Muslims aboard buses for deportation.

Relishing the latest U.N. humiliation, Gen. Ratko Mladic arrived on the heels of his infantry after they seized the main peacekeeper camp that once protected the civilians of the U.N.-declared ``safe area'' around Srebrenica.

The Serbs took charge of 40,000 hungry and desperate refugees from Srebrenica who sought refuge at the camp just north of the town, in Potocari. They herded women, children and the elderly aboard buses and trucks, separating them from all men over 16, who were held for interrogation.

The Serb rebels requested fuel for the convoys, but a U.N. official said their request would be denied.

``We are not going to assist this in any way,'' said Kris Janowski, a spokesman for the U.N. High Commissioner for Refugees. ``This pure `ethnic cleansing,' we cannot involve ourselves in this.''

A main purpose of the U.N. presence in Bosnia was to prevent combatants from persecuting and deporting civilians of other ethnicities. Muslim, Croat and Serb combatants have all been accused of such ``ethnic cleansing'' and other atrocities, but Serbs have by far received the most blame.

The Dutch U.N. troops charged with protecting the civilians could do little. A Serb tank stood at the gate to the camp, and mortars and rocket launchers were aimed at the refugees, who waited in the 88-degree heat.

The peacekeepers shared their rations _ food and water meant for half the U.N. contingent of 400. The UNHCR arranged for shipment of 22 tons of food and other aid to help the refugees.

``They are in desperate need of food, clothing and medicines,'' said UNHCR spokesman Ron Redmond.

The peacekeepers pleaded in vain with Mladic to abandon plans to take all males over 16 to the nearby town of Bratunac, where Mladic said they would be ``screened for war crimes,'' according to U.N. spokesman Alexander Ivanko.

Mladic himself, along with other Bosnian Serb leaders, has been named a suspected war criminal by a special U.N. tribunal in The Hague, Netherlands.

Three convoys of buses ferried 3,000 refugees from the U.N. base at Potocari toward Kladanj, a town held by the Muslim-led government 28 miles to the west, said Lt. Col. Gary Coward, another U.N. spokesman.

Bosnian Serb television showed about 20,000 people, mostly women, children and elderly people, waiting to board. Some women ran toward the buses, and when they were filled, the Serbs brought in trucks.

Mladic, protected by muscular bodyguards, approached a boy, patted him on the head and asked for his name, then told a group of refugees: ``There is nothing for you to be afraid about. You can do whatever you want, either go or stay. No one will do you any harm.''

But he was clearly there to oversee their expulsion.

``Let's go. We're going now,'' a U.N. spokesman quoted Mladic as telling people.

Dutch peacekeepers went along with the convoys ``to ensure that the refugees don't suffer anymore,'' Coward said.

Nevertheless, the Serbs insisted the convoys stop where government-held territory began, forcing the exhausted refugees to walk the final 10 miles to Kladanj, U.N. officials said.

About 1,500 of the refugees arrived in the government-held ``safe area'' of Tuzla late Wednesday night.

Meanwhile, angry Bosnian Muslims were blockading a U.N. base to the northwest, preventing a U.N. team from receiving the convoy with food and medicine, said Capt. Harald Kjaerstad. The demonstrators were demanding that the United Nations retaliate for the Serb storming of Srebrenica.

The fall of Srebrenica, one of six U.N.-designated ``safe areas,'' was the latest in a humiliating series of events for the United Nations, and dramatically highlighted the weaknesses of the U.N. mission in Bosnia.

The Serbs took hostage an additional 16 Dutch peacekeepers after overrunning their positions late Tuesday and Wednesday, bringing the number of U.N. captives to 48.

The United Nations requested two NATO air assaults during the Srebrenica attack Tuesday, but called off a third after the Serbs threatened to kill the 30 peacekeepers they had already seized.

Later, a U.N. official said, the Serbs pressed their advantage, threatening to shell the thousands of people around the Potocari camp if NATO warplanes did not leave the area entirely. Again, their demand was met.

Bosnian President Alija Izetbegovic, fed up with what he called a lack of U.N. resolve, requested the resignation of Yasushi Akashi, the senior U.N. envoy in the former Yugoslavia, and demanded that the U.N. troops retake Srebrenica by force.

France said it would consider a military response to oust the Serbs from Srebrenica. British Foreign Secretary Malcolm Rifkind said Wednesday that Britain was waiting for more information from the French ``as to the details of what they have in mind.'' France and Britain have the most peacekeepers in Bosnia.

The U.N. Security Council voted unanimously to ask Secretary-General Boutros Boutros-Ghali to ``use all resources available'' to do that, but his chief military adviser said the task was beyond the U.N. troops in Bosnia.

Bosnian Serb leader Radovan Karadzic dismissed calls for him to withdraw from the enclave.

``What withdrawal? From our country?'' he asked. ``Srebrenica is our country.''

The war erupted in 1992 with a Serb revolt against Bosnia's secession from Serbia-dominated Yugoslavia. Bosnian Serb nationalists want to merge the 70 percent of Bosnia they hold with Serbia, and have expelled hundreds of thousands of non-Serbs from their holdings.