GOMA, Democratic Republic of Congo (Reuters) -Repeated tremors shook the Congolese city of Goma on Monday, unnerving families still reeling from a volcano eruption at the weekend that destroyed nearby villages, displaced thousands and killed at least 15 people.
Mount Nyiragongo, one of the world's most active and dangerous volcanoes, erupted on Saturday evening, sending a smouldering wall of lava half a mile wide downhill towards the city of 2 million people.
The lava flow stopped a few hundred metres short of the city limits, but wrecked 17 villages on the way, cut the principal electricity supply and blocked a major road, disrupting aid deliveries.
A string of small earthquakes has since struck the city, the surrounding region in eastern Democratic Republic of Congo and across the border into Rwanda.
One reached a 5.1 magnitude at 10:37 a.m. (0837 GMT) on Monday, according to the Rwanda Seismic Monitor, which is managed by the Rwanda Mines, Petroleum and Gas Board.
Shops briefly reopened in Goma on Monday but many closed again as the tremors grew more severe and residents worried that these could trigger another eruption.
Tremors struck every 30 minutes in the city from midday on Sunday. In Rwanda, a Reuters reporter saw several buildings damaged by the tremors.
Dario Tedesco, a volcanologist based in Goma, told Reuters the earthquakes were caused by tectonic plates realigning after the eruption, and that the risk of a second eruption was small.
AID HAMPERED
"It's exactly what we saw in 2002 where we felt many earthquakes in the aftermath," he said referring to the volcano's last eruption.
But authorities in Goma urged caution.
"In view of the earthquake, which is becoming more severe, parents are asked not to send their children to school until further notice," army spokesman Guillaume Ndjike said.
About 1,000 houses were destroyed and more than 5,000 people displaced by the eruption, the United Nations aid coordinator in Congo, Diego Zorrilla, told Reuters on Monday.
Goma is a hub for humanitarian aid in Congo's east, but delivery efforts have been hindered by the closure of Goma's airport, Zorrilla said, and it could be days before the main road from Goma to the north reopens, he added.
"We have humanitarian operations in North Kivu that target 1.4 million people, that risk being disrupted if access to and from Goma is not restored," Zorrilla said.
Fifteen people were killed on Saturday, including nine in a traffic accident as residents fled, four who tried to escape Munzenze prison in Goma and two who were burned to death, the government said.
The death toll is likely to rise considerably. Residents told Reuters about relatives lying dead the wreckage or missing. UNICEF said around 170 children were among the missing.
(Reporting by Olivia Acland and Hereward Holland; Writing by Cooper Inveen; Editing by Edward McAllister, Jane Merriman and Andrew Heavens)