At least 12 people were killed and 21 injured when a bus drove off a mountainside about 220 kilometers south of the Albanian capital, Tirana.
A police source said 33 people -- mostly university students and professors -- were on the bus and the casualty toll could be higher.
Fourteen of the injured are reportedly in serious condition.
According to reports, the bus was traveling from Elbasan to Saranda when it crashed near the town of Himare on May 21.
The cause of the crash has not been determined, although local media quoted a survivor as saying the bus had been going "very fast" just prior to the accident.
Prime Minister Sali Berisha, who is attending the NATO summit in Chicago, has sent his condolences.
The government has declared May 22 a national day of mourning
Based on reporting by AP and AFP