Nigeria morgue scene of sorrow after plane crash

"It's going to be messy," Shuaib said.

Late Monday, emergency workers recovered both the flight data recorder and the cockpit voice recorder, said Tunji Oketunbi, a spokesman for the Accident Investigation Bureau, which probes airplane crashes in Nigeria.

"We will take them abroad for decoding and that will help our analysis," Oketunbi said Tuesday. "We will know what happened to the aircraft shortly before it crashed."

An investigator from the U.S. National Transportation Safety Board also is expected to join Nigerian authorities on Tuesday to help them determine a cause for the crash, Oketunbi said.

President Goodluck Jonathan wept as he visited the crash site Monday and pledged to make air travel safer, but the crash called into question the government's ability to protect its citizens and enforce regulations in a nation with a history of aviation disasters.

Some U.S. citizens were aboard the flight, State Department spokesman Mark Toner said, but he could not provide a firm number. A woman from West Hartford, Connecticut, her husband and four young children died on board the flight. The Tuesday edition of the Hartford Courant newspaper identified the family as Maimuna Anyene, her Nigerian husband Onyeke, and their children, a 5 month old, 1-year-old twins and a 3 year old.

Family members said Americans Josephine Onita and Jennifer Onita of Missouri City, Texas were killed in the crash. The family said the sisters were in Lagos to attend a wedding.

Others killed in the crash included at least four Chinese citizens, two Lebanese nationals and one French citizen, officials said.

Associated Press writers Bashir Adigun in Abuja, Nigeria and Mike Graczyk in Houston, Texas contributed to this report. Jon Gambrell can be reached at www.twitter.com/jongambrellap.