The employees have been identified as John Salman of Kent, Michael Hemmer of Federal Way, Ricky E. Wilson and Ronald Richey.

Jim Proulx of Boeing said he could not discuss the fate of the employees until Boeing had determined their status and informed their families.

The families of Salman and Hemmer, who were contacted by KIRO, said they did not know their loved one's fates.

At least nine people were killed, including two pilots, and 50 others were injured when the plane went down. Six of the victims suffered critical injuries.

The employees were flying from Istanbul to Amsterdam.

Investigators in Amsterdam are working under a spotlight around the Turkish Airlines jet. One Dutch investigator said the plane apparently lost speed and "fell out of the sky." When the plane hit the ground, it broke into pieces.

Boeing is sending a team to provide technical support to the investigation.