Video of Dzhokar Tsarnaev In Boat

An infrared video was released by the Boston police revealing the hiding place of Dzhokhar Tsarnaev in a boat in the backyard of a house in the Boston suburb of Watertown.

Tamerlan Tsarnaev being investigated for possible links to Caucasus Emirate

In August 2012, soon after returning from a long visit to Russia, Tsarnaev created a YouTube channel with links to a number of videos.

Two videos under a category labeled “Terrorists” were deleted. It’s not clear when or by whom. But analysis by CNN and the SITE Intelligence Institute has uncovered a screen grab from one of those videos. It features members of the group Imarat Kavkaz — identifiable by the logo on their shirts. Imarat Kavkaz is the most potent militant Islamist group in Russia’s North Caucasus region — which includes Chechnya and Dagestan.

Separately, a U.S. intelligence source tells CNN that investigators are looking into whether Tsarnaev had any connections with the group — known in English as the Caucasus Emirate. The source says Tsarnaev had several computer-links to the group in his social media activities and investigators are looking into the possibility he may have received “operational plans” from this group.