National Transportation Safety Board officials say they are not yet able to gather the flight recorder as part of the UPS plane that crashed Wednesday morning was still burning into the evening. Further, it's not expected that the NTSB will determine the cause of the crash for some time.The A300 cargo plane crashed near an airport in Birmingham, Alabama, and was en route from Louisville. Both crew members have been reported dead.(Related: WFPL's previous coverage of the plane crash)The NTSB is on the ground collecting evidence. "We are not [in Birmingham] to conduct any analysis and we will not be determining cause of the accident. Nor will we, in any case, speculate on the accident," said NTSB member Robert Sumwalt at a press conference Wednesday evening.The plane crashed into a grassy field and no one on the ground was reported hurt. The NTSB is seeking witnesses or anyone who may have found wreckage near their homes. The board has also sent a staffer to Louisville as part of its research.