Three frontline healthcare workers have mysteriously fallen out of hospital windows in Russia over the past two weeks, heightening public attention to the working conditions for doctors and medical professionals amid the coronavirus pandemic.

Two of those healthcare workers are dead, and one remains hospitalized. All three incidents, which are being investigated by Russian law enforcement authorities, have prompted intense discussion in the Russian press and on social media.

Alexander Shulepov, an ambulance doctor in Voronezh, a city about 320 miles south of Moscow, is in serious condition after falling from a hospital window on Saturday. Local state television, citing regional health officials, said he fell out of second-floor window of the Novousmanskaya hospital, where he worked and was receiving treatment after testing positive for coronavirus.

Shulepov was hospitalized for coronavirus on April 22, the same day he and his colleague Alexander Kosyakin posted a video online saying that Shulepov had been forced to continue working after testing positive for coronavirus.

Kosyakin had previously criticized hospital administration for protective gear shortages on his social media and was questioned by the police for allegedly spreading fake news.

Kosyakin confirmed these details to CNN in an interview.

"[Shulepov] is an intensive care unit, as far as I know in a serious condition, last time I spoke to him was on the 30th of April, we checked in with each other," Kosyakin told CNN. "He felt fine, he was getting ready to get discharged from the hospital ... and all of a sudden this happened, it's not clear why and what for, so many questions that I don't even have the answer to."

Police have not responded to CNN's request for comment.

The Novousmanskaya hospital said in a statement that Shulepov had been taken off a shift as soon as he informed the hospital administration about his positive diagnosis and was offered hospitalization in the infectious diseases ward.

Three days later, Shulepov retracted his previous statements, saying that in his video with Kosyakin he was "overwhelmed by emotions." The second video Shulepov recorded featured Igor Potanin, the head doctor of the Novousmanskaya hospital, who said his medical staff has enough protective equipment.

"I spoke about this to the department's employees: I won't let anyone go to outpatients or inpatients if we don't have enough means of protection, I told them I'd go myself there, but I will not send anyone," Potanin said.

Shulepov was the third health worker in Russia to fall out of a window in the past two weeks.

On May 1, Elena Nepomnyashchaya, the acting head doctor of a hospital in the Siberian city of Krasnoyarsk, died after spending a week in intensive care, the regional department of the Health Ministry said in a statement.

Local TV station TVK Krasnoyarsk reported at the time that Nepomnyashchaya allegedly fell out of a window during a meeting with regional health officials, during which they discussed turning the clinic into a coronavirus facility.

Nepomnyashchaya was reported to have opposed those changes due to the lack of protective gear in the hospital. The Health Ministry's regional health department denied the allegations in a statement, adding that the hospital is in "reserve" for coronavirus patients and its staff has been trained and equipped. The hospital did not respond to CNN's requests for comment.

On April 24, Natalya Lebedeva, head of the emergency medical service at Star City, the main training base for Russia's cosmonauts, died in a hospital after a fall.

The hospital within the Federal Biomedical Agency, which says it treated her for suspected coronavirus, released a statement that "a tragic accident" occurred, without elaborating. The hospital did not respond to CNN's request for comment.

In the statement, the hospital said, "She was a true professional in her field, saving human lives every day!"

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