Helicopter operations need to be scrutinised in order to avoid any disaster or tragedy in the future, said Deputy Transport Minister Datuk Ab Aziz Kaprawi.

He said the number of helicopter tragedies in the country was a bit worrying.

"Probably (the helicopter operations) need to be more refined and include the pilots. Definitely (relevant parties) need to identify the weaknesses in helicopter operations," he told reporters after breaking fast with the media personnel here Monday.

Asked on the latest development on the helicopter crash in Sebuyau, Sarawak on May 5, Ab. Aziz said the main frame of the helicopther was still missing.

The search would continue, he added.

Last week the preliminary report on the helicopter AS350 crash in the Batang Lupar indicated that the most probable impact point was in the river as bodies of all occupants, pilot and several helicopter parts, were recovered in the river.

The report released by the Air Accident Investigation Bureau (AAIB) also said there was a possibility of the helicopter's main frame being submerged in the river.

The ill-fated helicopter that crashed in Batang Lupar, Sebuyau was carrying five passengers - Plantation Industries and Commodities Deputy Minister Tan Sri Noriah Kasnon, her husband Asmuni Abdullah, and her bodyguard Ahmad Sobri Harun.

Two others in the helicopter were Plantation Industries and Commodities Ministry secretary-general Datuk Dr Sundaran Annamalai and Kuala Kangsar Member of Parliament Datuk Wan Mohammad Khair-il Anuar Wan Ahmad, who was also Malaysian Palm Oil Board chairman.

The helicopter was piloted by Captain Rudolf Rex Ragas.

In April last year, Rompin Member of Parliament Tan Sri Jamaluddin Jarjis was among the six people involved in a deadly helicopter crash in Semenyih, Selangor.