By CBS3 Staff

LUZERNE COUNTY, Pa. (CBS/AP) — Federal authorities in Pennsylvania say a small number of military ballots cast for President Donald Trump were discarded in Luzerne County. The U.S. Attorney’s Office of the Middle District of Pennsylvania says an investigation was launched Monday following reports of potential issues with a small number of mail-in ballots at the Luzerne County Board of Elections.

The FBI and Pennsylvania State Police have conducted interviews and recovered and reviewed physical evidence. Authorities say Luzerne County election officials have been cooperative.

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Authorities can confirm that a small number of military ballots were discarded and investigators have recovered nine ballots so far.

Some of the discarded ballots can be attributed to specific voters and some cannot. Authorities say seven of the nine ballots were cast for Trump.

Authorities say two of the discarded ballots had been resealed inside their appropriate envelopes by Luzerne elections staff prior to recovery by the FBI and the contents of those two ballots are unknown.

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The U.S. Attorney’s Office is continuing to investigate.

Trump himself has repeatedly blasted mail-in voting as rife with fraud, which elections experts say is rare. Despite his objections to mail-in voting, Trump has voted by mail previously.

Pennsylvania is one of the highly-contested battleground states heading into the presidential election. Trump narrowly won the state in 2016.

According to the latest CBS News Battleground Tracker, Democratic nominee Joe Biden holds a five-point lead over Trump — 52% to 47%.

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(© Copyright 2020 CBS Broadcasting Inc. All Rights Reserved. The Associated Press contributed to this report.)