ATHENS, Greece (AP) — Greece’s armed forces declared three days of national mourning after five members of a military rescue team were killed in a road accident in flood-hit Libya.

The bodies of the five — three military officials and two civilians — were flown back to a military base near Athens early on Monday, together with 13 injured team members who were taken to military hospitals in the Greek capital.

A bus transporting the Greek team crashed on Sunday en route to the city of Derna, which has suffered devastating flood damage. The bus hit an oncoming car, also killing three Libyan passengers, according to Libyan officials.

“We are all shocked by the deaths of rescuers who were participating in a humanitarian mission to show solidarity to the suffering Libyan people,” Greek President Katerina Sakellaropoulou said. “I am deeply saddened by their unexpected death.”

Heavy rains from Mediterranean storm Daniel caused massive flooding across eastern Libya a week ago. It overwhelmed the two dams, sending a wall of water through the coastal city of Derna, killing at least 11,000 people. More than 10,000 people are missing, and presumed dead. Entire neighborhoods have been destroyed as flood waters swept bridges, cars and people out to sea.

Before crossing the Mediterranean, the storm caused extensive damage in central Greece, where many areas remain flooded.