Russia says thwarts plot to kill Putin ally

Russia says thwarts plot to kill Putin ally

In a statement, the FSB said the two Russian nationals were detained on May 16 in possession of two hand grenades and more than 500 grams of plastic explosives.

Matviyenko, 58, told reporters that people could try to use attacks against politicians to undermine stability.

"You just cannot rule out any terrorist acts against politicians and employees of the state to undermine the situation and attract attention," she said.

"The law enforcement agencies have worked very professionally, as you can see," Matviyenko was shown saying with a smile on state television.

State news channel Vesti-24 showed FSB footage of the suspects being searched. They lay face-down on the ground as FSB offers found a grenade and a lump of what looked like plastic explosives.

Kremlin supporters have sounded warnings that extremist groups and radicals financed from abroad could try to undermine political stability.

But many opponents tend to view such "plot" reports as an attempt by a group in power to raise the political temperature in the 2007-08 election period for political ends.

Matviyenko, a former diplomat who has become one of the most influential women in Russia, helped Putin cement Kremlin control over the northern city where was born.

Elected governor of St Petersburg in 2003, she had a second, five-year term approved by Putin in December.

Known for her eye-catching dress sense, Matviyenko has sought to boost St Petersburg's commercial and political importance and recover some of its pre-revolutionary image.

She said she had no plans to increase her own security because of the threat: "I feel calm."

Putin, credited with imposing stability after the chaos which accompanied the fall of the Soviet Union, says he will step down when his second four-year terms ends in 2008.