Federal judge orders postal inspectors to several states, including Pa., to ensure no mail-in ballot is left behind

PHILADELPHIA (WPVI) -- A federal judge has ordered the U.S. Postal Service to send inspectors to several processing facilities in key battleground states - including Pennsylvania - to ensure that no mail-in ballot is left behind.

U.S. Judge Emmet Sullivan ruled Tuesday that the Postal Service must "sweep the facilities between 12:30 p.m. and 3:00 p.m. to ensure that no ballots have been held up and that any identified ballots are immediately sent out for delivery."

Additionally, those inspectors are ordered to report back to the court by 4:30 p.m. "confirming, in the most efficient manner available, that sweeps were conducted and that no ballots were left behind," Sullivan wrote.

Full list of locations: Central Pennsylvania, Philadelphia, Detroit, Colorado/Wyoming, Atlanta, Houston, Alabama, Northern New England, Greater South Carolina, South Florida, Lakeland, and Arizona.

ABC News contributed to this report.