Exclusive: As authorities closed in on Dzhokar A. Tsarnaev, the 19-year-old Chechen identified as the second alleged suspect in the Boston Marathon bombing, The Boston Globe urged its employees to stay safe.

The Globe sports a stable of journalistic thoroughbreds, many of whom have hunted for finite scoops and detail in dangerous places. Take former Moscow bureau chief David Filipov, riding on horseback through Taliban territory during the outbreak of the war in Afghanistan. Or reporter David Abel, who was at the center of Monday’s blast zone and remained on scene to gather the news.

“As a news organization, there are unique demands on our employees, but please comply with these directives if possible,” publisher Christopher M. Mayer wrote in a Friday morning memo, obtained by FishbowlNY. “Your safety is our first priority.”

Tsarnaev and the man identified as his 26-year-old brother, Tamerlan, are believed to be the suspects seen planting pressure cooker explosives in videos and photographs from before the dual explosions that killed three and injured more than 150 at Monday’s race. The elder Tsarnaev was killed in a shootout with police after allegedly robbed a 7-11 and killed a police officer at the Massachusetts Institute of Technology.

By Friday morning, police had surrounded a house in the Boston suburb of Watertown, where the remaining suspect is thought to be holed up.

A third arrest, of someone identified by NPR’s Dina Temple-Raston as an accomplice and not a suspect, was also made Friday morning.

Boston’s taxi services and MBTA system were shut down on Friday during the manhunt.

Read the full staff memo after the jump:

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