(CNN) -- The radical leftist terror group -- Revolutionary People's Liberation Party, or DHKP-C -- has claimed responsibility for Friday's suicide bombing at the U.S. Embassy in Ankara, Turkey.

In a statement on its website, the group said, "E. Alisan Sanli has become a martyr after accomplishing the action on the American Embassy in Ankara."

"We are going to build the future with sacrifices," the statement said.

The blast killed a Turkish guard and wounded a television journalist.

While theories have been floated, neither Turkish nor U.S. authorities have detailed why they think Sanli blew himself up.

Sanli received bomb-making training somewhere in Europe in the mid-1990s, according to Hasam Selim Ozertem, a security expert at the International Strategic Research Organization in Ankara. Turkish officials say that as a result of counterterrorism operations on Turkish soil, DHKP-C became increasingly active among the Turkish diaspora in Europe.

Sanli returned to Turkey in 1997 and was subsequently involved in attacks on the Istanbul police headquarters and senior military officials using anti-tank weapons. After being arrested, Sanli went on a lengthy hunger strike and was released from jail in 2002 because of a neurological disorder.

Whatever Sanli's rationale, the explosion spurred security clampdowns at diplomatic facilities in Turkey, plus messages of condolences and solidarity. Turkish Prime Minster Recep Tayyip Erdogan called it an attack "against the peace and welfare of our country."

Yet the violence reverberated well beyond Turkey's borders, however, especially in the nation whose embassy was targeted.

The spotlight on U.S. diplomatic installations was already intense after violence last September in Egypt, Tunisia and Libya, where Ambassador Christopher Stevens was one of four Americans killed in Benghazi.

CNN's Tim Lister and Talia Kayali contributed to this report.

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