Editor's note: This article by Matthew Cox originally appeared on Military.com, a leading source of news for the military and veteran community.

The Pentagon announced Friday that it will deploy about 3,600 additional military personnel to support COVID-19 vaccination sites around the country.

Defense Secretary Lloyd Austin has authorized an additional 20 teams to support a Federal Emergency Management Agency request -- one that could ultimately require close to 19,000 service members to assist at vaccine sites, Pentagon spokesman John Kirby told reporters Friday.

Austin approved five teams on Feb. 4. The first is made up of soldiers from Fort Carson, Colorado, Kirby said. That team has deployed to California and will be "operational, we expect, by Monday supporting a mega-vaccination site in Los Angeles," he added.

The new total of 25 teams brings the troop strength supporting the FEMA effort to 4,700 personnel, Kirby said.

The 20 newly authorized teams will be made up of 10 type-one teams, each consisting of 222 personnel supporting mega-vaccination sites, he said, adding that the other 10 will be smaller type-two teams of 139 personnel supporting smaller vaccination sites.

"These 20 teams are being organized to support FEMA-identified sites and will be deployed as requirements evolve," Kirby said.

The troops supporting FEMA will join the more than 26,000 National Guard members and 3,000 active-duty personnel who have been supporting COVID efforts over the last year, he added.

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Details are still being worked out, Kirby said, but most of the personnel for the teams could come from the active force.

"We don't have sites for all these additional 20 teams that the secretary authorized," he said. “Sourcing isn’t complete, but I would expect that many of these teams will be sourced out of the active component.”

The demand from FEMA could ultimately require 100 teams, bringing the total up to approximately 18,800 personnel, Kirby said.

"This will be a deliberate and phased approach," he said. "What we are trying to do is to make sure that when FEMA has identified sites that we are properly poised and ready to support those sites."

The Pentagon is working with U.S. Northern Command to make sure that the troops on these teams receive the training and resources they need to be ready for the mission, Kirby said.

"What we are trying to do is to be ready when we are needed," he said.