President Donald Trump’s campaign said it sued to block Pennsylvania from certifying the result of last week’s election, claiming a variety of voting irregularities, including that observers weren’t granted sufficient access to the ballot counting process as required under state law.

The campaign claims Pennsylvania violated the Elections Clause of the Constitution by counting a record number of mail-in ballots in a procedure that lacked transparency due to restrictions from the coronavirus. The filing of the lawsuit Monday couldn’t be confirmed in court records.

“Nearly 2.65 million votes were cast through a ‘mail-in’ process that lacked all of the hallmarks of transparency and verifiability that were present for in-person voters,” the campaign said in the complaint.

The complaint is the latest effort by Trump and the Republican party to cast doubt on the outcome of an election in which his Democratic challenger Joe Biden has been declared the winner. Trump has been arguing for months that a surge in use of mail-in ballots would lead to a rigged election.

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