The wreckage of Bargishev's car

GROZNY, Russia (CNN) -- The head of a special police anti-kidnapping force in Russia's breakaway Chechnya region died of wounds inflicted when his car was blown up on Sunday, Chechen officials said.

"(Shaid Bargishev) died about 40 minutes ago. His relatives have collected his body," Supyan Akhmadov, head of the anti-kidnapping force's investigative department, told reporters in the Chechen capital Grozny.

Bargishev died in the hospital after losing both legs in the blast outside the anti-kidnapping department office in Grozny, according to Mairbek Vachagayev, spokesman for Chechen president Aslan Maskhadov.

Two bodyguards also were hurt in the explosion, which police said they were treating as a "terrorist act."

The attack came as the security unit was poised to launch a major operation to free more than 100 hostages.

Several hostages have been freed recently from the republic, including 24 Russian soldiers and an English couple. Most of the releases have been facilitated by Russian financier Boris Berezovsky, though details of his involvement have been unclear.

Husein Zabrailov, an investigator who worked with Bargishev in the anti-kidnapping department, blamed Sunday's bombing on the recent hostage releases.

"The accident is a result of the work of the department," he said.

More than 100 people are still being held captive in Chechnya, including three Britons, a New Zealander and a Turk, according to the Interfax news agency.

Chechnya, where rebels fought a bloody independence war against Russia in 1994-96, conducts its own affairs and has seen a sharp rise in violent crime and hostage-taking, usually by criminal gangs for ransom.

Maskhadov on Sunday ordered law enforcement officials to step up efforts against criminal groups, the ITAR-Tass news agency reported.

"The assassination attempt and threats will not force us to stop. The fight against organized crime will continue until we completely eliminate this evil," Maskhadov told ITAR-Tass.

Akhmadov vowed to find those behind Sunday's blast. "They will be stopped and severely punished," he told a news conference in Grozny.

The Associated Press and Reuters contributed to this report.