The United Nations has warned that as many as 400,000 people have fled the Congolese city of Goma amid fears of a fresh volcanic eruption at nearby Mount Nyiragongo.

On Thursday, officials ordered the city to be partially evacuated, worried lava flows into Lake Kivu would generate a tsunami and toxic gas cloud.

The city is half empty. Goma looks like a ghost town. The massive evacuation of people was triggered on Thursday by a rise in tremors coming from Mount Nyiragongo - and fears that it could erupt once more.

Hundreds of thousands have now fled. The town of Sake is full - and so they are moving into neighbouring Rwanda, the Virunga National park or even across Lake Kivu.

Aid agencies are responding, with displaced people requiring food, shelter, water and sanitation.

There were less tremors on Thursday night - leading some to hope this could be coming to an end. But still, ominous sounds can be heard coming from Mount Nyiragongo.