SINGAPORE » The girlfriend of a U.S. software engineer whose parents insist he was murdered in Singapore said at a coroner’s inquest Monday (Sunday in Hawaii) that he had been unhappy at work and feared “heavy hands coming after him.”

Police have said Shane Truman Todd killed himself. State counsel presented evidence of links to suicide websites on his laptop and suicide letters written to his family members and loved ones.

Parents Rick and Mary Todd, who attended the inquest, told The Associated Press in March they consider the evidence fake. They believe he may have been murdered over his research in the U.S. into material used to make heat-resistant semiconductors, a technology with both civilian and military applications. The Todds have received assistance in the case from U.S. senators and the FBI.

Todd’s girlfriend, Shirley Sarmiento, found his body in his apartment June 24. The 31-year-old was hanging from a black strap that was fashioned into a noose and secured to a door, the state counsel’s opening statement said. The statement said Todd had no visible signs of injury on his body except redness on his forearms and legs. Police found no signs of forced entry into the apartment.

Sarmiento, a Filipino nurse working in Singapore, was the first of at least 36 witnesses who will be called to testify during the inquest, including personal friends, IME colleagues and forensic doctors. The inquest is expected to last 12 days, and its conclusions cannot be appealed.

She testified that Shane had often confided in her about his suspected depression and that he had mounting unhappiness with the “dishonest environment” in his workplace. She also mentioned he feared “heavy hands coming after him.”

Todd’s parents were somber throughout the proceedings, occasionally getting up to speak with their lawyers.

Rick Todd said his son in early 2012 had expressed concerns to his parents that he was being asked to compromise U.S. security. But he said Shane Todd wasn’t specific.

His parents traveled from their home in the U.S. state of Montana to Singapore days after his death and found his belongings packed as if he intended to leave for good. They said they saw no signs of a hanging, such as marks on the door.

Mary Todd also said a suicide note that police showed her and her husband was obviously fake because it thanked the Institute of Microelectronics, a former employer he had grown to hate, and had other false details.

The Todds have said that while they were in Singapore, they found a hard drive missed by investigators that contained thousands of documents their son had backed up from his work computer. After having it analyzed by a computer forensics expert, they found a draft of a project outline between the Institute of Microelectronics and Chinese telecom giant Huawei on the development of a device that utilized gallium nitride.

The heat-resistant material has civilian uses in products like LED screens and cellphone towers, and military applications in things like radar and satellite systems. Todd had been trained in the U.S. on proprietary equipment that produces the material but is restricted for export because of the potential military applications.

Huawei has said it had no cooperation with the Institute of Microelectronics related to gallium nitride. IME has said neither Todd nor the company was involved in any classified research.

Todd’s parents had sought for the FBI to lead the investigation into the scientist’s death, though the status of any assistance it has provided is classified.