Early voting kicked off in Philadelphia on Tuesday where residents in the key battleground state were met with problems at the polls.

Voters who arrived at centers early Tuesday morning had to wait hours to cast their votes, according to a report from The Philadelphia Inquirer.

Delays were allegedly triggered by problems with the voter database, the newspaper reported, which prevented the processing and approval of mail-in ballot applications, and the printing of other materials.

Satellite election offices have been set up around the city to help facilitate voting by allowing i people to register to vote, and request, complete and submit mail-in ballots. Voters can also drop off ballots at satellite offices.

By midday, six of seven locations were online, according to the Inquirer. Additional locations are expected to open on a rolling basis.

City officials did not immediately return Fox News’ request for comment.

PENNSYLVANIA JUDGE HALTS USPS CUTS AHEAD OF 2020 ELECTION AMID MAIL-IN VOTING WORRIES

Hillary Clinton won a smaller share of votes in Philadelphia in the 2016 election when compared with former President Barack Obama in 2012, but she did secure more overall votes than Donald Trump in the urban center. Trump, however, narrowly won Pennsylvania.

Pennsylvania has emerged as key swing state once again in the November election, where there have already been concerns raised about the voting process.

On Monday, Republicans filed an emergency application asking the Supreme Court to block the state from counting mail-in ballots received after Election Day. Currently, absentee ballots received by Friday, Nov. 6 would be counted.

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Further, U.S. District Judge Gerald A. McHugh Jr. granted an injunction to halt operational changes at the USPS that have delayed mail services, following similar rulings in several other states.

The Department of Justice initiated an investigation into an incident in Pennsylvania where several mail-in ballots were found in the trash. An inquiry found that a contractor incorrectly discarded them.

President Trump has repeated unfounded concerns about the mail-in voting process.