A passenger plane has crashed into a two-storey building in densely populated Lagos city, Nigeria's commercial hub.
A source at the national emergency management agency said the aircraft belonged to privately-owned domestic carrier Dana Air and had 147 people on board.
Femi Oke-Osanyinpolu, Lagos state emergency state manager, said on Sunday that casualty numbers are unknown.
Harold Denuren, head of the Nigerian Civil Aviation Authority, said the flight was heading from Lagos to Abuja, the capital. "I don't believe there are any survivors," he said.
It was unclear how many people were on board the plane or in the building, located just north of the airport.
An Associated Press reporter saw parts of the plane's seat signs scattered around. The rest of the plane was cratered into the apartment building.
Firefighters tried to put out the smoldering flames of a jet engine and carried at least one corpse from the building that continued to crumble. Thousands of people looked on.
Two firetrucks and about 50 rescue personnel were at the site about an hour after the plane went down. A military helicopter flew overhead.
Lagos airport has been shut down and passengers awaiting further flights told to go home.
Al Jazeera's Yvonne Ndege, reporting from Abjua, said people on the ground in Lagos believe it may have hit a power line and crashed into a building. She said there are pictures on the internet of huge plumes of smoke across the Lagos skyline.
"NEMA (the National Emergency Management Agency) has been alerted to an air crash in the Ishaga area of Agege, Lagos," NEMA spokesman Yushua Shuaib said.
Witnesses said they saw the plane strike a building and burst into flames.
The weather in Lagos on Sunday was clear and sunny.
Lagos' international airport is a major hub for West Africa and saw 2.3 million passengers pass through it in 2009, according to the most recent statistics provided by the Federal Airports Authority of Nigeria.
In August 2010, the US announced it had given Nigeria the FAA's Category 1 status, its top safety rating that allows the nation's domestic carriers to fly directly to the US.
The Nigerian government said it also now has full radar coverage of the entire nation. However, in a nation where the state-run electricity company is in tatters, state power and diesel generators sometimes both fail at airports, making radar screens go blank.
This latest incident came after another plane crash on Saturday night in the capital of the nearby West African nation of Ghana, which saw a cargo plane overshoot a runway and hit a passenger bus, killing at least 10 people.
The Allied Air cargo plane had departed from Lagos and was to land in Accra.
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