KUALA LUMPUR, March 17 — More US law enforcement officials are complaining that manpower and technical expertise offered to investigate missing Malaysia Airlines flight MH370 are running into a Malaysian wall.

With Malaysia announcing that the Boeing 777-200ER was deliberately diverted for a yet inconclusive reason, American investigators said the county’s refusal to accept offers in the “unprecedented mystery” is forcing them to rely on the limited personnel already in the country, the New York Times reported yesterday.

“There’s not a whole lot we can do absent of a request from them for more help or a development that relates to information we may have,” an unnamed law enforcement official told the newspaper.

At the moment, their investigative efforts were limited to two Federal Bureau of Investigation (FBI) agents stationed in Malaysia prior to the disappearance of the plane on March 8.

But the US investigators said that with just two men, their quest for clues about why someone took the plane with 239 people on-board away from its planned flight route has come up empty.

The baffling circumstances behind the plane’s disappearance has also thrown up numerous possibilities that need to be eliminated — ranging from an alleged al-Qaeda plot to hijack a Malaysian plane to possible separatist unrest from China’s Xinjiang region and possible crew suicide.

On Saturday, Malaysian police searched the homes of both the MH370 pilots and took a flight simulator the captain had built to mimic the cockpit of the 777-200ER.

But US officials again complained that they have not learned about any findings from the “experts” who examined the simulator.

Unnamed US sources voiced suspicion that Malaysia is refusing additional help to avoid appearing that they required assistance in the high-profile probe.

Western complaints of Malaysia’s alleged refusal to accept more investigative aid began on Friday when anonymous agents claimed that Interpol, the global police co-operation agency, was repeatedly told its offers to help were unnecessary.

This escalated yesterday when a senior US lawmaker, Congressman Peter King, said the FBI has communicated its “frustrations” with the Malaysian government’s co-operation or lack thereof.

King then demanded that the US National Transportation Safety Board (NTSB), the Federal Aviation Administration (FAA) and the FBI, along with Interpol, be given a “hands on” role in the investigation currently led by Malaysia.

Malaysia maintains that it welcomes any and all help offered, and that it worked with “all agencies”.