Mr. Davis said police set up a perimeter around that boat when they arrived.

WSJ: Relief in Boston as New Details Emerge in Hunt for Suspected Bombers

Get the perimeter set up now. 10.52.58 Tim Pearce Hey, stop that car!

BBC

When backup arrived, the suspect had disappeared, prompting officers to set up a perimeter, Santa Cruz County Sheriff Phil Wowak said.

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Police said that the Franklin Street house was about a block outside a perimeter they set up to try to contain Mr. Tsarnaev after the initial shootout.

WSJ: Relief in Boston as New Details Emerge in Hunt for Suspected Bombers

He ordered Major Khalil and the DynCorp men to set up a good security perimeter.

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He managed to elude us by being just slightly outside of the perimeter that we set up.

WSJ: Relief in Boston as New Details Emerge in Hunt for Suspected Bombers

Authorities late Sunday located the second inmate and said a security perimeter had been set up around the area where 33-year-old Danny Provencal has been found.

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