China has demanded an investigation into the death of a scientist after “hostile questioning” by US investigators.

Danhao Wang, a semiconductor researcher at the University of Michigan, was found dead on campus in the early hours of March 20 after falling from the upper floor of a building, according to a police statement.

The University of Michigan’s Division of Police and Public Safety said the death was being investigated as a “possible act of self-harm”.

But Lin Jiang, a Chinese foreign ministry spokesman, said the US had “overstretched the concept of national security for political manipulation” and called on authorities to carry out a full investigation.

On Thursday, Liu Pengyu, a spokesman for the Chinese embassy in the US, told the BBC that China had “repeatedly lodged solemn representations with relevant US government agencies and universities regarding this case”.

He also urged Chinese students in the US to “heighten their safety awareness” and “handle US law enforcement actions appropriately”.

The Chinese consulate in Chicago, which oversees the jurisdiction of the University of Michigan, said that it had “protested multiple times to relevant departments of the US government and the university”.

Karen Thole, the dean of the College of Engineering, said: ‘This is an active police investigation, and we have no further information to share regarding the circumstances surrounding his death.”

US authorities have not released details of Mr Wang’s death or the reasons why he had been taken in for questioning.

A spokesman for the university’s Division of Police and Public Safety said the full police case would not be released until toxicology reports were complete.

The US has been taking measures to address foreign influence, especially allegations of Chinese espionage in recent years.

The University of Michigan has been under particular scrutiny after at least five of its students from China were charged with smuggling biological material into the US.

The university is also being investigated for allegedly misreporting the foreign funding it had received from the Chinese government.

The university has stated: “It is important to note that the university has received no funding from the Chinese government in relation to research conducted by the accused individuals.

“We have and will continue to co-operate with federal law enforcement in its ongoing investigation and prosecution.”

Six days after Mr Wang’s death, Domenico Grasso, the interim president at the University of Michigan, appeared before the US House committee on education and workforce to respond to questions surrounding Chinese espionage within American universities.

He told Congress that the university continued to strengthen its background checks for foreign students and staff, and reinforced policies to protect sensitive material.

Mr Wang was a postdoctoral fellow in the lab of Zetian Mi, an electrical and computer engineering professor, whose research focused on the use of semiconductors in high-power and extreme conditions.

He had been working at the University of Michigan since 2022, according to his LinkedIn profile. Before moving to the US, he had received his PhD in electrical and electronics engineering at the University of Science and Technology of China.

Dr Thole wrote: “His loss is felt deeply not only by those who knew him here at the university, but also everyone who understands his potential to have contributed to breakthroughs in science that would have positively impacted people around the world.”

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