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MOSCOW, May 11 (RIA Novosti) - Russia's security agencies prevented a series of terrorist attacks in early May and seized more than 113 kilograms (250lb) of explosives, the national anti-terrorism committee said Thursday.

"Since March 2006, the committee began receiving information about preparations of a series of terrorist attacks... during the celebrations of Orthodox Easter, May 1 and Victory Day [May 9]," the committee said. "In this connection, committee chairman Nikolai Patrushev decided to step up counter-terrorism efforts on all directions."

The committee said that the law enforcement agencies had detained 74 and eliminated 12 terrorists, mainly in the south of the country.

The committee, which was set up in February under the chairmanship of domestic security chief Patrushev, also said more than 30,000 people, 6,000 houses and 7,000 cars had been checked during operations in the run-up to the May public holidays, when a number of public events were held, in particular to mark the anniversary of the end of World War II.

President of Chechnya Akhmad Kadyrov was assassinated in 2004 attending one such function in the republic's capital, Grozny, on May 9 and 43 people attending a parade were killed in a bomb attack in the Daghestani town of Kaspiisk on the same date in 2002.

The committee said police had discovered 27 caches with weapons, equipment, communication devices, food and medicines and seized more than 113kg of explosives, 12 grenade-launchers, and plans to plant explosive devices near public buildings.