The U.S. Food and Drug Administration is requesting that at least two blood centers in Florida halt all collections stemming from fears tied to the Zika virus.

Reports are the counties in question are now being probed for possible transmissions of the virus, which has wreaked havoc across the globe over the last several months.

In an emergency notice sent to centers in Miami-Dade and Broward counties and posted on the agency's website, FDA officials requested that the centers "cease collecting blood immediately."

The measure is expected to remain in place until the facilities can test individual units of blood donated in those centers with a special virus donor screening test or until the headquarters can be equipped with special investigational technology.

Zika Concerns Mounting 

The FDA actions come just hours after it was made public that authorities in Florida are now investigating two new Zika cases that could have been spread by local mosquitoes.

"These may be the first cases of local Zika virus transmission by mosquitoes in the continental United States," the FDA said in its notice.

The Florida surgeon general and all the major blood collection industry organizations have been made aware of the request, with the main organization, OneBlood, indicating it had also been made aware of the suspected non-travel-related Zika case still under investigation in South Florida.

OneBlood officials stressed if the case is confirmed, it would stop collections in the affected zip code and bring in blood from unaffected areas of the city.

Upgrades in Testing 

On the company website, assurances note authorities now plan to test a portion of its collected blood for the Zika virus and to allow hospitals to have access to thoroughly screened blood products from unaffected areas to use with their patients at high risk such as pregnant women.

FDA officials deemed their request "a prudent measure to help assure the safety of blood and blood products,"