FBI agents in the United States have agreed to help with forensic analysis after last week's crash of a Russian airliner in Egypt.
The British government suspects a bomb exploded on board, killing all 224 passengers and crew.
Egyptian crash investigators are complaining about the lack of intelligence sharing - and insist it is too early to say what caused the disaster.
Amid the confusion and uncertainty, thousands of tourists are still stranded in Sharm el-Sheikh trying to fly home.
So, who can we trust to tell the truth? And how much politics is involved?
Presenter: Jane Dutton
Martin Reardon - Senior vice president of the Soufan Group
Igor Sutyagin - Senior research fellow at the Royal United Services Institute
Oliver McGee - Former US deputy assistant secretary for transportation and aviation specialist
Source: Al Jazeera