Dmitry Kostyukov for TIME
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The following photographs were taken between May 12-15, 2013. A man arrives at the village mosque in Utamysh, the home of Russian-born Canadian William Plotnikov, who was killed in a shootout with Russian counterterrorism forces in July 2012.Dmitry Kostyukov for TIME
Dmitry Kostyukov for TIME
People pray in the mosque visited by William Plotnikov in village Utamysh, where  he lived and died
Dagestan youth train in  one of the box and wrestling school in Makhachkala on May 14, 2013.
A boy do sport exircises on May 12, 2013 in front of house where Mahmud Nidal was killed in a "spetsoperatsia" in Makhachkala.
A grave of one of respectfull muslims is seen on May 12, 2013 near village Utamysh, where  William Plotnikov lived and died
The beach outside Makhachkala is seen on May 12, 2013 where Tamerlan was withhis friends.
Women pray in main mosque of Dagestan in Makhachkala on May 14, 2013.
An owner of a farm  where William Plotnikov was killed with his friend stand near burned out buildings destroed during anti-terror operation near village Utamysh, where Plotnikov lived and died
Two herders ride near the road from Kizlyar to Makhachkala on May 13, 2013.
The grave of William Plotnikov is seen on May 12, 2013 in village UTAMYSH, where William Plotnikov lived and died
Dagestan boys Parkour at the beach in Makhachkala on May 15, 2013.
A woman watch the fish at the market in Makhachkala on May 14, 2013.
A house where Tamerlan Tsarnaev use to live with his father during his staing in Dagestan is seen in Makhachkala on May 15, 2013.
Zubeidat Tsarnaeva walks near the sea in Makhachkala on May 15, 2013.
The following photographs were taken between May 12-15, 2013. A man arrives at the village mosque in Utamysh, the home of Russian-born Canadian William Plotnikov, who was killed in
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Dmitry Kostyukov for TIME
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What Tsarnaev Saw: Dagestan by Dmitry Kostyukov

May 16, 2013

On April 19, when the FBI announced that two brothers from southern Russia had bombed the Boston Marathon, the world's attention quickly turned to where these brothers had come from — a lush strip of highlands called Dagestan, which stretches along the western shore of the Caspian Sea. The elder of the two suspected bombers, Tamerlan Tsarnaev, had spent half of last year in this region of Russia, visiting his parents and reconnecting with his relatives. He also spent a lot of time hanging out with local adherents of Salafism, the fundamentalist brand of Islam that Tsarnaev also seems to have embraced.

Since the bombings in Boston, TIME has spent three weeks in Dagestan trying to learn what, if anything, the region's Islamists had to do with Tsarnaev's radicalization (to read the article, which is available to subscribers, click here). The search wound through nearly a dozen cities, towns and villages in Dagestan, along the rutted roads of the Caucasus mountains and into the neighboring region of Chechnya. It went inside the local Salafi mosques and the homes and neighborhoods of their congregants. What emerged was the image of a region trapped in a spiral of violence, one perpetuated as much by local security services as by the militants they hunt.

The region's insurgency and counterinsurgency have killed thousands of people over the last decade and shaped the lives of many more. They also shaped the ideas of jihad that Tsarnaev brought with him to Dagestan last year, as well as the beliefs that he apparently took back to Boston.

Simon Shuster is TIME’s Moscow reporter. Follow him on Twitter @shustry.

Dmitry Kostyukov is a freelance photographer based in Moscow. Kostyukov previously covered conflict in Georgia, Afghanistan and Israel for AFP.

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