MOSCOW // The suicide bomber who killed 35 people and wounded 180 at Moscow's largest airport was a 20-year-old man from the volatile southern Caucasus region, Russian investigators said Saturday.
Breaking a five-day silence over the investigation, federal investigators also said foreigners were deliberately targeted, marking an ominous new tactic in Russia's losing battle with extremism.
Islamist rebels from the Caucasus, a group of mountainous Russian provinces that are beset with an entrenched separatist insurgency, had been widely suspected in the attack at Domodedovo Airport.
Saturday's statement from federal investigators confirmed a suicide blast involving a bomb containing shrapnel. While authorities say they know the identity of the perpetrator, they suggested they still don't know who masterminded the attacks.
"Despite the fact that we know the name of the terrorist, we won't name him today ... since investigative searches are ongoing to identify and detain the organisers and accomplices of the terrorist act," the statement said.
Investigators also confirmed fears that foreigners in Russia had for the first time entered the terrorists' crosshairs; the victims included one person each from Britain, Germany, Austria, Ukraine, Tajikistan, Kyrgyzstan and Uzbekistan. There were at least 16 Russians among the dead.
"It was no accident that the terrorist act was carried out in the international arrivals hall. According to the investigation, the terrorist act was aim first and foremost at foreign citizens," the statement said.
No one has yet claimed responsibility, however, for the blast, the latest in a surge of attacks that the Kremlin appears helpless to stop. Critics say attacks have risen sixfold since Vladimir Putin became president, on a ticket to fight the scourge of terrorism, in 2000.
The Interfax news agency on Friday cited an unidentified law enforcement source as saying that surveillance video showed an unaccompanied male suspected suicide bomber, clad in a black jacket and baseball cap, standing in the area for about 15 minutes before the blast.
Some media have shown photos of a severed head believed to be that of the bomber and say the head has been sent to a forensic laboratory for DNA analysis.
After the Domodedovo blast, suspicion initially fell on Chechen insurgents. However, Prime Minister Vladimir Putin said preliminary evidence showed no connection with Chechnya.
Caucasus rebels have claimed responsibility for a number of deadly attacks over the years, including a double suicide bombing on the capital's subway system in March 2010 that killed 40 people. They also have hit Domodedovo Airport before, with two suicide bombers slipping through its security in 2004 and boarding two planes that exploded in mid-air, killing 90 people.
The violence stemming from the predominantly Muslim Caucasus region originates from two bloody separatist wars in Chechnya in the past 15 years. Federal forces wiped out the large-scale resistance, driving the insurgency into the mountains and into neighbouring provinces. The rebels seek an independent Caucasus emirate that adheres to Shariah law.
The rebels still mount regular attacks on police and security forces in the region, according to police reports. Human rights activists say their violence is provoked by a savage crackdown on peaceful civilians by authorities in the region, and hold Chechen President Ramzan Kadyrov and his feared private army to blame. Kadyrov, a former rebel himself until he switched sides and was subsequently installed by the Kremlin as president, denies being behind disappearances, torture and extra-judicial killings that rights activists say plague the region.
The Caucasus hosts at least 100 ethnicities, including Chechens, who resisted Tsarist conquest of the region for hundreds of years.
Since the Domodedovo blast, a half-dozen transport and police officials have been fired. President Dmitry Medvedev said after the blast that Domodedovo's security was in a "state of anarchy."
The attack stained Russia's image at a vulnerable time, coming just before Mr Medvedev's appearance at the Davos World Economic Forum to try to woo international investment. The explosion also called into question Russia's ability to safely host major international events such as the 2014 Winter Olympics and the 2018 World Cup.