The terrorist threat still exists in Russia, President Dmitry Medvedev said yesterday, after a suicide attack in southern Russia killed 12 people and injured about 40 others Thursday.

"This event has shown that the terrorist threat remains," Medvedev told a session on law enforcement issues in St. Petersburg.

Although active terrorist activities have been suppressed, the environment for such crimes still exists, he said.

"We should investigate what has happened as quickly as possible," the Interfax news agency quoted Medvedev as saying.

The president has instructed the National Anti-Terrorist Committee, the Prosecutor General's Office and other relevant agencies to investigate the accident and report to him personally.

A female suicide bomber blew herself up Thursday near a marketplace in Vladikavkaz, the capital of the North Caucasus region of North Ossetia, which borders turbulent Chechnya and Georgia's breakaway region of South Ossetia.