Ghana's defense and environment ministers died Wednesday in the crash of a helicopter, with no survivors reported, the presidency said after the aircraft, which was carrying three crew members and five passengers, went missing.

The death of Edward Omane Boamah, responsible for defense, and Ibrahim Murtala Mohammed, responsible for the environment, was confirmed by the head of Ghana's presidential office, Julius Debrah, according to the international press.

The president's chief of staff, Julius Debrah, on behalf of the government which considered the accident a national tragedy, expressed condolences and solidarity with the victims' families.

The accident took place in the Adansi Akrofuom district, where the aircraft, a Chinese military helicopter model Z-9, crashed due to unknown causes.

Following the plane crash, the Ghanaian authorities have opened investigations into the case and declared three days of national mourning from Thursday, during which all flags must be flown at half-mast.