Several arrested with suspected links to St Petersburg suicide bomber

Latest: 12am: Russian investigators have arrested several people suspected of links to a suicide bomber accused of attacking the St Petersburg subway earlier this week.

Update: 12am: Russian investigators have arrested several people suspected of links to a suicide bomber accused of attacking the St Petersburg subway earlier this week.

The investigators said they found elements of an explosive device in the apartment where they lived.

The Investigative Committee said the suspects are residents of the former Soviet Central Asia region like the bomber, 22-year-old Akbarzhon Dzhalilov, a native of Kyrgyzstan.

The impoverished, predominantly Muslim countries in Central Asia are seen as fertile ground for Islamic extremists, and thousands of their residents are believed to have joined the Islamic State group in Syria and Iraq.

The committee, the nation's top criminal investigation agency, said investigators also found objects that would help advance the probe during a search of the home on St Petersburg's eastern outskirts.

Russian news agencies reported that law enforcement agencies arrested three people.

The building's residents had been evacuated before explosives experts went in to check the site. Konstantin Serov, the chief administrator in the city district where the building is located, told Russian news agencies that police deactivated an explosive device at the apartment.

Police in the city are on high alert following Monday's explosion that killed the attacker and 13 other people and wounded 55 others.

Thursday's arrests came a day after law enforcement agencies detained eight Central Asian migrants suspected of acting as recruiters for the Islamic State group and al Qaida's Syria branch. The investigators found no immediate evidence of their involvement in the subway attack.

No one has claimed responsibility for the subway bombing, but Russian trains and planes have been targeted by bombings staged by Islamist militants in the past.

Earlier: Russian security officials are checking a suspicious object at an apartment building in St Petersburg following a suicide bombing on the city's subway system earlier in the week.

The Federal Security Service (FSB) said, according to Russian news agencies, that the object found in an apartment building on the eastern outskirts of the city early on Thursday could contain explosives.

Residents have been evacuated and explosives experts have started working at the scene.

Police in St Petersburg are on high alert following Monday's explosion that killed the attacker and 13 other people and injured a further 55.

On Wednesday, officers arrested eight Central Asian migrants suspected of acting as recruiters for the Islamic State group and al Qaida's Syria branch.

The investigators found no immediate evidence of their involvement in the subway attack.

- AP