A relative calm has returned to Goma in eastern Democratic Republic of Congo after rebels took control of the city, as several thousand people fled across the border to Rwanda, UN and humanitarian workers say.
Heavily armed M23 rebels paraded unchallenged through the centre of the city on Tuesday afternoon, after several days of fighting with UN-backed government forces.
Al Jazeera's Nazanine Moshiri, reporting from Goma, said there was an "eerie calm" in the city at night.
"M23 is very much embedded in strategic locations around the city," she said. "We are hearing reports of looting and intimidation by members of M23 but we haven't been able to verify this."
Earlier in the day, explosions and machine-gun fire rocked the lakeside city in North Kivu province as the rebels captured the city.
UN peacekeepers, known by their acronym MONUSCO, were not helping the government forces during Tuesday's battle because they do not have a mandate to engage the rebels, said Congolese military spokesman Olivier Hamuli, who expressed frustration over the lack of action by the peacekeepers.
"MONUSCO is keeping its defencive positions. They do not have the mandate to fight the M23. Unfortunately, the M23 did not obey the MONUSCO warnings and went past their positions [at the airport]. We ask that the MONUSCO do more,'' he said.
A UN spokesman said in New York that the nearly 1,500 UN peacekeepers in Goma held their fire to avoid triggering a battle. The peacekeepers "cannot substitute for the efforts of national forces" in DR Congo, said spokesman Eduardo del Buey.
In a radio broadcast, rebel spokesman Vianney Kazarama appealed for calm and ordered police and government soldiers to surrender on Wednesday morning at Goma's football stadium.
While the rebels claimed to have captured both the city and its airport, a UN spokesman said peacekeepers were in control of the airport and that UN forces were still on patrol in the city.
Tens of thousands of people have fled their homes or refugee camps around Goma, a city of about one million that is sheltering tens of thousands of refugees.
Aid group Oxfam described the situation as "a humanitarian catastrophe on a massive scale" and urged the international community to act. In a report, it said civilians were being raped, kidnapped and killed, as well as "being subjected to an unprecedented level" of extortion and looting.
Since the beginning of 2012, the conflict has uprooted close to 650,000 people in North and South Kivu provinces, according to UNHCR. More than 40,000 people have fled to Uganda and 15,000 to Rwanda since April.
Joseph Kabila, the country's president, urged people in Goma to "resist" the rebels' advancement.
"DR Congo is today confronted with a difficult situation," Kabila said on national television. "When a war is imposed, one has an obligation to resist. I ask that the entire population defend our sovereignty."
Kabila travelled to Uganda on Tuesday for talks with his counterpart, while regional foreign ministers began a meeting in Kampala focusing on renewed fighting around Goma.
Uganda last week closed its main border with DR Congo following accusations that Kampala was supporting the rebels in the east.
The Congolese government has accused both Uganda and Rwanda of supporting rebels who have been launching attacks in the country's North Kivu province since early this year. Both countries deny the charges.
DR Congo and Rwanda have already fought two wars, the most recent of which ended in 2003 after lasting nearly six years.