[Updated at 2 p.m.] The arrest is based on two videos showing images of the suspect, a federal law enforcement source told CNN contributor Fran Townsend.
[Updated at 1:46 p.m.] An arrest has been made in connection with Monday's Boston Marathon bombings, sources tell CNN's John King and CNN contributor Fran Townsend. King's source is with Boston law enforcement, he said; Townsend's source is with federal law enforcement.
[Updated at 1:44 p.m.] While we wait for more information about the possible suspect, some recent information to pass on about one of the three people who were killed in Monday's blasts: Boston University said Lingzi Lu, a graduate student in mathematics and statistics, was killed.
She and two friends were watching the race near the finish line when the blasts erupted, BU Today reported. The second student was in stable condition at Boston Medical Center; the third student was not hurt, it said.
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