By Gopal Sharma

KATHMANDU (Reuters) -Authorities in Nepal have retrieved the bodies of all six people killed in a helicopter crash on Tuesday, including five Mexican nationals, officials said, the latest in a series of air disasters to strike the Himalayan nation.

The cause of the crash near Likkhu, just northeast of the capital Kathmandu, was not yet known, the civil aviation regulator said, adding that the government would set up a committee to investigate.

The helicopter was operated by Manang Air, which ferries tourists seeking a view of the country's towering peaks, including Mount Everest, the world's tallest mountain.

Rescuers have retrieved the bodies of all six, said Basanta Bhattarai, the most senior bureaucrat in the district of Solukhumbu where the crash occurred.

"We have already dispatched four bodies to Kathmandu in a helicopter and are preparing to send the remaining two soon," Bhattarai told Reuters from the crash site.

He said rescuers had packed the dead in body bags and were waiting at a helipad for the weather to clear so the chopper could take off.

"The bodies were broken into pieces," said Sita Adhikari, another official in the region. A local witness, Nima Tshering Sherpa, said the helicopter had crashed into a bushy hillside.

An airport official, Teknath Sitoula, said a Nepali pilot and the five Mexican nationals had been on board.

"The helicopter took off ... in good weather," said Raju Neupane, a spokesperson for Manang Air. "The weather was not bad. Now we can't say what caused the crash. It will have to be investigated."

The mountainous country has a history of air crashes, as many airlines fly to small airports in remote hills and near peaks often shrouded in clouds and cut off from roads.

Nepal's worst air crash in 30 years killed 71 people in January, when a plane went down near the tourist city of Pokhara.

(Reporting by Gopal Sharma; Writing by Shilpa Jamkhandikar; Editing by Ed Osmond, Clarence Fernandez and Mark Heinrich)