Two homeless men were found dead on subway trains in New York City over the weekend, leading to additional concerns about the spread of the coronavirus.

According to The New York Post, transit workers first found the body of a 56-year-old man, whose identity has not been made public, on Friday night on a C train at the 168th Street station in Washington Heights.

On Saturday morning, a passerby found another man, Robert Mangual, “unconscious and unresponsive.” Police said the 61-year-old man was pronounced dead after being found on a 4 train at the Utica Avenue station in Brooklyn. 

Yann Hicks, a Metropolitan Transportation Authority train operator and a union representative, said there has been an increasing concern about the homeless presence during the outbreak.

“What it adds up to for us is, what is the cause of the death of these two people?” Hicks told The Post. “Is it coronavirus? Overdose?” 

The train operator said he has "to walk through seven to 10 cars just to find a clean car and be socially distant from vagrants on seats.”

Train conductor Joanne Green said, “there is a lot of homeless people on the trains and I am very scared daily."

"People have on masks, but most don’t," Green told the New York Daily News. "My co-workers and I are very vulnerable to these conditions and would like to see something done. It takes a toll on us as well.”

According to The Post, at least 98 MTA workers have died from the coronavirus. Twenty-six deaths were also reported on MTA subways from January to April,  compared to 19 during the same period last year. Eleven of the 26 deaths this year were attributed to natural causes, while nine fell under the same category last year. 

In regards to the two men who died during the weekend, police said the cause of death hasn't been determined in each case and preliminary investigations didn't find any signs of trauma or criminality.

The pandemic has caused subway ridership to decrease by 93%, the Daily News reported. Last week, Gov. Andrew Cuomo said train services will now be shut down from 1 a.m to 5 a.m. daily, reserving the time for disinfection.

“You never had a challenge of disinfecting every train every 24 hours,” Cuomo said in a press briefing. “It can best be done by stopping train service from 1 a.m. to 5 a.m. every night.”

According to the Daily News, the subway system is losing overnight service for the first time in its 115-year history. 

“These tragedies are heartbreaking and we are fully cooperating with the NYPD on their investigation,” MTA spokesman Ken Lovett said in a statement. “We have repeatedly said the subways are no replacement for a shelter and if these two individuals were indeed homeless, as suspected, it’s clear more needs to be done by the city to ensure all New Yorkers have access to needed shelter and services.”

Tony Utano, the president of Transport Workers Union Local 100, also issued a statement, saying “you have to get the homeless out of the subway and provide them the services they need, including safe shelter and medical treatment.”

“Transit workers are worried they could catch the coronavirus from the homeless who are camped out in the system,” Utano said. "That’s why we support closing the system overnight during the pandemic for intensified cleaning and disinfecting.”