Cuban officials say they have found one of the two black boxes from a plane that crashed near Havana's main airport, killing more than 100 people, in "good condition".
Transport Minister Adel Yzquierdo says he hopes the second device will be recovered soon.
The Boeing 737, which was nearly 40 years old, was carrying 105 passengers and six crew members.
Three women survived the crash, but are said to be in a critical condition.
The incident is Cuba's worst air disaster in decades, and two days of national mourning began on Saturday.
Officials said investigators are combing through the plane's wreckage at the crash site, a field some 20km (12 miles) south of Havana. The black box which has already been recovered will hold key data and information about what happened on the flight.