About 10 officers from the NYPD, as well as several from the Port Authority Police Department, arrived in Boston on Wednesday to set up camp in some trailers at the intersection of Berkeley and Boylston Streets, near the site of Monday's bombings.
Joe Mancini, a spokesperson for the New York City Patrolmen's Benevolent Association, said that PBA President Pat Lynch and other PBA members traveled up there because they have a relationship with the Boston police union since September 11th.
"They supported us at 9/11 and we're returning the favor," Mancini explained.
They have a canteen, Mancini said, where they're handing out coffee and other refreshments for the investigators working tirelessly along the still blood-stained streets.
"Our department has, unfortunately, been down this road," Port Authority cop Ray Butler told the the Daily News.
Lynch said in a statement: "On 9/11, when our officers were needful, our brother and sister Boston police officers saw our need and responded. They fed us, they comforted us, and they backed us up. Now it's time to return the favor."
Mancini said the officer are working in shifts and staying at nearby hotels, and don't have any specific plans for when they'll return home.
"They'll be there for as long as the Boston PBA says, 'we need you,'" Mancini promised.
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