Singapore is seeking US assistance in probing the mysterious death of an American scientist reportedly involved in a project for a Chinese telecoms firm seen as a security risk by Washington.
Police confirmed they had asked the FBI to examine evidence from the family of Shane Todd, an electronics engineer found hanged in the city-state in June last year.
The family dispute an autopsy report that he committed suicide and fear he may have been murdered, saying they found computer files linking Todd's work before his death to China's Huawei Technologies, which denies involvement in any such project.
A police spokesman said they had asked Todd's family to share any evidence in their possession or have it reviewed by the FBI if they were "not comfortable" handing it over to the Singapore Police Force.
The US State Department said on Friday that Washington had offered FBI assistance to Singapore and was engaged in "frequent discussions" with the country's officials on the case.
The story first generated attention after Britain's Financial Times reported last month that Todd's parents suspected he may have been murdered due to his work at a top electronics research institute in Singapore.
It said he had been working on an advanced amplifier using gallium nitride (GaN), a tough semiconductor material, and that the technology could have commercial and military applications. It also said that two months before he died, Todd was given an antidepressant by a Singapore psychiatrist who found him under heavy stress.
Huawei said it was approached by Todd's ex-employer, the Institute of Microelectronics (IME), but "we do not have any cooperation with IME related to GaN."
It added: "Huawei does not do military equipment or technology, nor do we discuss it with partners. The development of GaN technology is commonplace across the entire telecommunications industry."
A US Congressional committee last year labelled Huawei and ZTE, another Chinese telecom firm, as potential national security threats that should be excluded from government contracts and barred from making acquisitions in the US.
The late scientist's parents Rick and Mary Todd have told US media of their suspicions about their 31-year-old son's death and lobbied officials in Washington to press for a deeper investigation.
Singapore police have classified Todd's case as an "unnatural death" and in such cases the final verdict is handed down after a coroner's inquest, which has yet to take place.
Todd worked from December 2010 to May last year for the IME, part of the Singapore government-funded Agency for Science, Technology and Research.
Agency managing director Raj Thampuran told The Straits Times "there were discussions, but no project ensued between IME and Huawei on amplifiers".