Nigeria began three days of mourning Monday after a plane crashed in Lagos Sunday, killing all 153 people on board.

The ruins of the commercial airliner continued to smolder Monday as emergency workers carried bodies and debris from the crash site in a residential neighborhood in Nigeria's largest city.

President Goodluck Jonathan has ordered a thorough investigation into the disaster.

The number of people possibly killed on the ground remains unclear.

Officials from Nigeria's Civil Aviation Authority say the Dana Airlines flight was traveling from Abuja to Lagos when it crashed into a two-story building in a densely populated area, setting other buildings on fire.

Media reports say chaos broke out after the crash, with rescue workers facing large crowds and aggressive soldiers, while trying to access the wreckage in the hunt for survivors.

Aviation officials say the pilot had radioed the Lagos control tower to declare an emergency just minutes before the crash.

China says six of its nationals were on the plane.

Dana Airlines is a domestic air carrier that operates a fleet of Boeing MD-83 aircraft for the hour-long flight from Abuja to Lagos.