A lava flow reached the airport of the Democratic Republic of Congo's eastern city of Goma early Sunday after the eruption of the Mount Nyiragongo volcano, an official said.
"The situation is deteriorating," an official from Virunga National Park — where the erupting volcano is located — said in a message to staff, which AFP was copied in on.
"Besides the lava flow in the north east (Kibumba / Rwanda), the flow is also descending on the town. It has now reached the airport," he said.
The official added that the lava flow was likely to reach the shores of Lake Kivu.
"The eruption of Nyiragongo is similar to the eruption in 2002," he added, asking all local residents near the airport to "evacuate without delay".
He said that at this stage, "the other districts of the city were not in danger" and the lava was unlikely to reach those areas.
Thousands of people had already left the city even before Mount Nyiragongo began spewing red smoke into the night sky, and officials activated an evacuation plan late Saturday.
The last time Nyiragongo erupted was January 17, 2002, killing more than a hundred people and covering almost all of the eastern part of Goma with lava, including half of the airport's landing strip.
Hundreds of thousands fled the city.
Goma sits on the mountain's southern flank and overlooks Lake Kivu.
The Goma region, which lies in North Kivu province, bordering Rwanda and Uganda, has six volcanoes, all higher than 3,000 metres