Russia probes metro bomber contacts as first victims buried

Leningrad Oblast: Russia staged raids on suspected contacts of the Saint Petersburg metro bomber Thursday, as the jittery city laid to rest the first of the 13 people killed in the attack.

Investigators said the raids targeted "several citizens of Central Asian republics, who had been in contact" with 22-year-old Akbarjon Djalilov, thought to be a Russian national born in Central Asian Kyrgyzstan.

"Objects relevant to the investigation were found during the search of the apartment where these people lived," said the powerful Investigative Committee. 

"They were all confiscated and sent for analysis."

No one has yet claimed responsibility for the blast that tore through a subway carriage in Russia`s second city on Monday.

Djalilov`s remains were found at the blast site and traces of his DNA were also discovered on a bag containing a bomb at another metro station that was successfully defused, investigators said. 

Investigative Committee chief Alexander Bastrykin has ordered officials to look into any potential "links" between the alleged attacker and the Islamic State (IS) group.

Jihadists from IS -- including foreign fighters from the ex-Soviet Central Asia and the Caucasus region -- have repeatedly threatened an attack on Russian soil in revenge for Moscow`s military backing of Syrian leader Bashar al-Assad.

And in a sign of a city on edge, the FSB security service told TASS news agency it had found and defused a "homemade explosive device" during a search in a Saint Petersburg apartment building. 

The authorities have not linked the discovery to Monday`s bombing.As the urgent probe into the attack continued, relatives and friends geared up to bury the victims as the country held a third day of official mourning.

The first set to be laid to rest was 50-year-old dollmaker Irina Medyantseva, with mourners gathering in a town just outside Saint Petersburg for her funeral. 

The attack has shaken the authorities and rattled Saint Petersburg just two months before it hosts the opening game of the Confederations Cup football tournament, a curtain raiser for the 2018 World Cup in the country.

Russia suffered a wave of brutal attacks in the 1990s and 2000s blamed mainly on a rebellion in Chechnya that morphed from a separatist uprising into an Islamist insurgency. 

The country`s transport network -- including the metro in Moscow -- was hit repeatedly by suicide bombers leaving scores dead. 

But there had been no attacks against a major city since blasts in the southern city of Volgograd in December 2013, weeks ahead of the Sochi Winter Olympic Games. 

IS, however, has struck at Russia abroad, claiming a bomb attack in October 2015 that blew a passenger jet packed with holidaymakers returning to Saint Petersburg out of the air over Egypt, killing all 224 people onboard.

In an apparently unrelated event an explosive device injured a homeless man in the southern city of Rostov-on-Don.

An officially sanctioned solidarity rally with Saint Petersburg and concert is set to be held Thursday evening by the Kremlin walls in Moscow.