The Pentagon is evaluating a request from the Federal Emergency Management Agency (FEMA) to provide help in administering COVID-19 vaccines, a spokesman said on Thursday.

On Monday, President Joe Biden said he believed it was possible to have 150 million doses of vaccine administered in his first 100 days in office.

“Given the significance of the request, it will be reviewed urgently but carefully to determine what DoD assets can safely be made available to support the effort,” Pentagon spokesman John Kirby said in a statement.

While the statement did not provide the number of troops that could be involved, a U.S. official told Reuters it could number in the thousands.

The pandemic, which has killed over 420,000 Americans, is currently infecting more than 173,000 people daily and has left millions out of work.

Using the military to fight the coronavirus is not new. At its peak under former President Donald Trump, more than 47,000 National Guard troops were supporting COVID operations across the country and about 20,000 continue to help.

The Army Corps of Engineers has also built thousands of rooms around the country to assist hospitals with the strain caused by spread of the coronavirus.