Nigerian transportation officials say human error may have contributed to an airline crash that killed at least 99 people.

Roland Iyayi, Director General of the Nigerian Airspace Management Agency, told VOA Monday the pilot of the Boeing 727 airliner ignored instructions to delay takeoff because of bad weather. He said two other airlines on the runway obeyed instructions not to fly.

Authorities say 106 passengers and crew were on board the Boeing 737 jetliner when it crashed shortly after takeoff Sunday from Abuja's national airport. Rescuers pulled seven badly burned survivors from the wreckage.

Among the dead was the Sultan of the northern state of Sokoto, Muhammadu Maccido. He headed Nigeria's Supreme Council of Islamic Affairs and was regarded as the spiritual leader of Nigeria's 70 million Muslims.

Other dignitaries on the plane include the sultan's son - who was a senator - the deputy governor of Sokoto, and a son of former Nigerian President Shehu Shagari.

Nigerian President Olusegun Obasanjo expressed his condolences and has ordered a full investigation into the crash. Nigerians begin a three-day period of national mourning, Monday.

The flight, headed for Sokoto, was operated by A.D.C. (Aviation Development Corporation) airline, a popular domestic airline with an aging fleet.

This was the fourth significant air crash in Nigeria in just over a year.

Some information for this report was provided by AFP, AP and Reuters.