KUALA LUMPUR, June 1 — Victoria Police took 86 minutes before they could storm the Malaysian Airlines flight MH128 that turned back to Melbourne because of a bungle among the officers, the Sydney Morning Herald (SMH) reported today.

Citing an anonymous source, the report said the plane was stranded on the tarmac because of an on-call officer who failed to respond to an emergency message, followed by the response team later unable to locate firearms and body armour.

The report said that the police were poorly briefed and thought for nearly an hour that the man may have been carrying an explosive device, when it was reported later to be just a powerbank.

The source also said that the police were not informed that the man had already been restrained by crew and passengers.

Chief Commissioner of Victoria Police Graham Ashton was reported saying that they were told that there was more than one perpetrator on the plane, with the possibility of more bombs.

In a separate report, the daily quoted several other passengers criticising the police for taking close to two hours to help defuse the tense situation.

One passenger, Selena Brown, said the police took over 90 minutes to board the plane and detain the alleged bomber, although they were already on stationed outside the plane.

"We were told police would take 10 minutes but it was over an hour. I thought it was really disappointing only because we weren’t updated all the time.

"We could see them all outside and they weren’t coming on to the plane and we didn’t know why,” she reportedly told SMH.

The police later explained that the incident was not being investigated as terrorism, as the object in question was not a bomb. They reportedly said that the man who made the threat has a history of mental illness.

Melbourne Airport remains in a lockdown over the incident and all flights headed there have been diverted to other airports.

The incident came just months after Canberra called off the search for missing Flight MH370 carrying 239 passengers and crew, after a vast underwater hunt off Australia’s west coast failed to find the plane.