The US Geological Survey reported a 6.8 magnitude quake struck near the town of Kalemie in the Democratic Republic of Congo (DRC), about 975 kilometres southwest of the Kenyan capital Nairobi, at 1219 GMT on Monday.
Residents of Kalemie, a town with a population of 200,000 on the shores of Lake Tanganyika, reported at least one death and several injuries and said mud-brick houses had collapsed in poor neighbourhoods.
“A child died when the house he was in collapsed during the earthquake. Several other people have broken limbs and are in hospital,” Kalemie community leader Fidel Muteba said.
Besides the DRC, tremors were felt in Kenya, Burundi, Rwanda, Tanzania and Zambia, countries connected by a string of lakes and mountains, many of them active volcanoes.
The US embassy in the Zambian capital Lusaka warned of the possibility of a tsunami on Lake Tanganyika, citing information from the Pacific Tsunami warning centre.
Hundreds of people evacuated office buildings in the centre of Nairobi after the tremors and the streets were clogged with people trying to drive away from the city centre.
“People came running down — scared — because you don’t know what it is. You’re moving this way and that,” said one witness, Tabitha Nyambati.
“We actually saw the building shaking and seats moving in the building,” said Peter Ragula, 37, a Nairobi salesman.
Officials in Tanzania said the tremor was felt there but they had received no reports of any injuries.
The quake was also felt in the Rwandan capital Kigali and in Burundi’s capital Bujumbura.
In Kigali, internet cafe attendant Abdul Hamidou said: “The desktop screens were moving, my chair was shaking making me feel dizzy, and all of a sudden I saw customers running out”.
Monday’s earthquake was the first fatal seismic event in the region since 2002 when Africa’s deadliest eruption in 25 years swept away thousands of homes and killed 25 people after Mount Nyiragongo exploded near the eastern DRC town of Goma.
Africa’s most active volcanoes are set amid the Rift Valley, a vast geological and geographical feature that runs north to south for 5,000 km along the earth’s crust from northern Syria to central Mozambique.