Documents that contained sensitive information about President Biden's trip to Northern Ireland this week were found on a Belfast street.

The documents were from Police Service of Northern Ireland and included a rough itinerary relating to Mr. Biden's visit and contained names and positions of police officials, according to a U.S. Secret Service official. The documents did not contain any Secret Service information, its security plan or list any agency personnel, the official said.

There was "nothing hurting" Secret Service's security plans in the documents, the official said.

The official said there has been no breach of Secret Service systems related to incident and no plans to change Mr. Biden's schedule or travel plans.

"The Police Service of Northern Ireland (PSNI) informed the Secret Service of media reports regarding a potentially sensitive document, which may contain law-enforcement material," Secret Service said in a statement. "While we do not discuss the specifics of any protective operation, the President's movements were not affected by these reports."

A Northern Ireland police spokesperson said an investigation into the breach is underway.

"We take the safety of visiting dignitaries, members of the public and our officers and staff extremely seriously and will put the appropriate actions in place," the spokesperson said.

Mr. Biden is in Northern Ireland to mark the 25th anniversary of the Good Friday Agreement, the U.S. brokered peace deal that effectively ended decades of conflict in the region. He will then travel to the Republic of Ireland to address the Dublin parliament and visit his ancestral hometowns.

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