Amid growing speculation over the deaths and disappearances of 11 American scientists, concerns are mounting as a similar pattern of deaths has emerged in China.

In many of the Chinese cases, the causes of death are recorded as accidents, sickness, or unexplained incidents. 

And while these explanations appear straightforward individually, taken together they are drawing increased scrutiny. 

One of the most puzzling cases is that of Feng Yanghe, a 38-year-old defence technology professor who died in July 2023. 

He had reportedly been working on simulations related to a potential Taiwan invasion before his death in a late-night car crash in Beijing, Newsweek reports.

Official accounts state that Feng had been leaving a work meeting when the crash occurred at around 2.35 am. 

But speculation grew after his obituary described the scientist as having been 'sacrificed while performing official duties,' wording that some observers found unusual for what was described as a traffic accident.

Further attention was drawn by his burial in a high-profile cemetery typically reserved for national figures. Such honors are rarely associated with standard accident cases.

Reports point to at least nine similar deaths of Chinese scientists in recent years.

Many of them were working in highly sensitive fields, including military artificial intelligence, space defence and hypersonic weapons.

Among them was Zhang Xiaoxin, a space expert who died in a reported car accident in December 2024. 

Chen Shuming, a specialist in microelectronics, also died in a similar incident in 2018.

And chemist Zhou Guangyuan passed away in December 2023, with no official cause of death disclosed. 

Other cases include Yan Hong, who died after an illness and Fang Daining, who died following what was described as an unexpected medical episode abroad. They both worked in the field of hypersonics.

Meanwhile, drone expert Zhang Daibing and data scientist Liu Donghao also died under circumstances that remain unclear.

However, despite the growing attention, officials have given no indication that foul play is involved. 

The deaths come as at least 11 American experts with ties to NASA, nuclear research, aerospace programs and classified projects have vanished or turned up dead in recent years.

Many of the individuals held top security clearances, granting them access to sensitive information on space missions, nuclear technology or advanced defence systems, prompting speculation about possible 'sinister' connections.

This disturbing pattern first emerged after retired Air Force General William Neil McCasland vanished on February 28.

He was last seen leaving his New Mexico home without his phone, wearable devices or glasses less than two months ago. He was only carrying a pistol and his wife told 911 dispatchers that it appeared he was trying 'not to be found.'

The strange circumstances surrounding the general's disappearance were almost identical to four other missing person cases taking place in the Southwest between May and August last year.

Concerningly, all four have been tied to McCasland through his work overseeing the Air Force Research Lab (AFRL), based at Wright-Patterson Air Force Base, which has been rumored to study extraterrestrial technology since the 1947 Roswell UFO crash.

An anonymous source told the Daily Mail that Garcia was a government contractor working for the Kansas City National Security Campus (KCNSC), a major facility in Albuquerque that manufactures more than 80 percent of all the non-nuclear components that go into building the military's nuclear weapons.

While at Wright-Patterson, McCasland oversaw and reportedly approved the funding for scientist Monica Jacinto Reza's work on a space-age metal for rocket engines called Mondaloy.

Reza, 60, disappeared while hiking with friends in California on June 22 last year. She had just become the director of the Materials Processing Group at NASA's Jet Propulsion Laboratory.

Anthony Chavez and Melissa Casias both worked at the Los Alamos National Laboratory (LANL), one of the nation's most important nuclear research sites, and disappeared within weeks of each other last year.

Chavez, 79, worked at the lab until his retirement in 2017, although his role there has not been made clear. Casias, 54, was an active administrative assistant at the facility and is believed to have had top security clearance.

 Lawmakers are now demanding that the FBI, Pentagon, NASA and the Department of Energy open probes into the concerning deaths and disappearances, which included researchers from NASA's Jet Propulsion Laboratory and Los Alamos National Laboratory.

'The Committee on Oversight and Government Reform is investigating recent unconfirmed public reporting on the disappearance and death of individuals with access to sensitive US scientific information,' Republican chairman James Comer wrote in letters sent on Monday.

'These reports allege that at least ten individuals who “had a connection to US nuclear secrets or rocket technology,” have “died or mysteriously vanished in recent years,"' he writes.

'If the reports are accurate, these deaths and disappearances may represent a grave threat to US national security and to US personnel with access to scientific secrets.'

Comer specifically notes the 'possible sinister connection between a string of mysterious deaths and disappearances which began in 2023.'

President Donald Trump said that he was briefed on the string of disappearances and deaths last week, saying that answers about the alarming cases should come out in the coming weeks.

'Well, I hope it is random, but we are going to know in the next week and a half,' Trump said when asked about the missing scientists last week.

'I just left a meeting on that subject, so pretty serious stuff. Hopefully, coincidence... but some of them were very important people, and we are going to look at it.'

The administration and the FBI are looking into the missing scientists, it was announced last week.

'In light of the recent and legitimate questions about these troubling cases, and President Trump’s commitment to the truth, the White House is actively working with all relevant agencies and the FBI to holistically review all of the cases together and identify any potential commonalities that may exist,' press secretary Karoline Leavitt said.