BOSTON (WHDH) — With the arraignment of Boston Marathon bombing suspect Dzhokhar Tsarnaev and the trial of reputed mobster James “Whitey” Bulger going on the same day, security was at unprecedented levels at the Moakley Federal Courthouse in South Boston Wednesday.

Tsarnaev arrived to the courthouse by police escort hours before his hearing, while Bulger’s racketeering trial was already underway.

U.S. Marshals and the FBI handled security at the courthouse. State police, Boston police and officers from the Department of Homeland Security assisted.

The courthouse was blanketed with officials, including police dogs and police on boats in the harbor.

Police told 7News, this was the first time they have had two high-profile suspects in the same courthouse at the same time. Bulger was in courtroom No. 11. His trial will go until 1 p.m. At 3:30 p.m., Tsarnaev will appear in the courtroom next door, No. 10.

Tsarnaev will be in courtroom No. 10 because it is one of the larger courtrooms in the courthouse to handle the large crowds that started gathering early Wednesday.

Officials are there to make sure Wednesday’s proceedings happen without any problems.

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