Kinshasa, May 24 : At least 15 people were killed after the eruption of Mount Nyiragongo volcano located on the outskirts of Goma city in the Democratic Republic of the Congo (DRC), according to the authorities. Government spokesman Patrick Muyaya said that 15 people were killed while fleeing following the explosion on May 22, reports Xinhua news agency. Nine people were killed in a truck rollover accident, while four others were prisoners trying to break the Munzenze central prison in Goma, the spokesman said. He added that two more people were burned to death on Sunday morning. DRC authorities are yet to release the assessed collateral damage caused by the eruption. Muyaya still urged residents to avoid non-essential activities while seismic activity in the area could still cause damage. Helicopters of the UN peacekeeping mission in the DRC made constant reconnaissance flights after the eruption over the crater to closely monitor the situation. According to local authorities, the lava flow came to a stop at around 4 a.m. on Sunday morning, while local residents started returning to their homes overnight. Around 3,000 people fled Goma for neighbouring Rwanda, while others headed for villages surrounding the city, including Sake. Right after the volcano erupted, the sky above Goma, with a population of nearly 2 million, was illuminated with orange flames. The electricity supply across much of the city was cut off. Goma is home to two active volcanoes -- Nyamulagira and Nyiragongo. The last time a major Nyiragongo eruption occurred was in 2002, when about 250 people were killed and 120,000 others were left homeless. /IANS