Dzhokhar Tsarnaev
Tsarnaev's throat injury, believed by some to be the result of a suicide attempt, prevents him from speaking, but reports say he's been communicating in writing. FBI

Police have taken the second Boston Marathon bombing suspect, Dzhokhar A. Tsarnaev, into custody, the Boston Police Department tweeted Friday shortly before 9 p.m. EDT.

The arrest brought an end to a lengthy and tense manhunt that swept through the Boston suburb of Watertown most of the day.

Tsarnaev was arrested after being cornered in a boat in a backyard by law-enforcement officers after a series of gunshots were reportedly heard in the area.

The gunshots were heard by CNN reporters at about 7:10 p.m., and the network then aired footage in which the rapid shots could be heard. Subsequently, both the Boston Globe and CNN reported that a source said the bombing suspect had been cornered.

The Globe initially reported that the suspect had been pinned down by police, but the newspaper changed its story shortly thereafter to say that sources said he was cornered in a boat in a Watertown backyard.

Police told reporters on the scene shortly before 7:10 p.m. to ignore their decision to lift the lockdown on the Watertown neighborhood a bit earlier in the day, and that folks in the area should stay inside their homes.

Shortly thereafter, CNN announced live on the air that a police source had told it that the suspect was cornered and that officers were deploying tear-gas in an effort to either draw the suspect out or get the individual to pass out.

Immediately following the gunfire, a large number of law-enforcement vehicles and officers headed in the direction of the shooting.

The world's eyes were focused on Watertown on Friday as authorities swept the neighborhood in search of the 19-year-old Boston Marathon bombing suspect.

The entire suburban community was locked down for most of the day by authorities, who urged all Boston-area residents to remain inside their homes until notified otherwise, as Tsarnaev was considered by law enforcement to be "armed and extremely dangerous," as FBI Special Agent Rick DesLauriers said this week.

Tsarnaev's 26-year-old brother Tamerlan Tsarnaev was killed overnight in a wild altercation with law-enforcement officers that left one Massachusetts Institute of Technology police officer dead and precipitated the massive manhunt.