ANKARA

The death toll from the crash of a medical transport helicopter into the sea in southwestern Japan over the weekend has risen to three, with authorities confirming two more fatalities Monday.

The helicopter, with six people on board, crashed off Nagasaki prefecture Sunday, with local authorities working to determine the exact cause of the accident, Kyodo News reported, citing the coast guard.

The death of an 86-year-old female patient was confirmed on the day of the incident, while a 68-year-old male family member accompanying her and a 34-year-old male doctor were also pronounced dead Monday.

The helicopter left the airport on the island of Tsushima in the prefecture around 1.30 p.m. local time Sunday and was scheduled to arrive at a hospital in Fukuoka, the largest city on the southwestern island of Kyushu, in 45 minutes.

Around 5.05 p.m., a coast guard patrol vessel found the helicopter floating upside down and rescued three people alive and conscious. The other three passengers were also retrieved but later confirmed dead.

The helicopter had previously been temporarily grounded to undergo safety checks after two people died in a crash in Fukuoka Prefecture linked to the same aviation firm last July, according to hospital authorities

The helicopter involved in the latest accident was inspected Friday and no irregularities were detected.

*Writing by Aamir Latif