VLADIKAVKAZ, Russia — Chechen rebels on Monday staged a series of attacks against pro-Moscow forces in the capital Grozny, killing four, as the death toll in last week's bombing of the Chechen government headquarters reportedly rose to 83.

As Chechnya began observing three days of mourning, NTV television reported that 83 people had been killed and more than 160 people wounded in the attack Friday, when suicide bombers rammed two explosives-filled trucks into the government compound in the capital Grozny. Some of the victims have been evacuated to Moscow and other cities to ease the burden on Grozny's overwhelmed hospitals.

Fifteen people remained in critical condition, the Interfax news agency said.

Violence continued in the city, with two Russian servicemen shot dead in the middle of a crowded market, a law enforcement official in Grozny said. The assailants fled.

A Chechen police officer and a Russian serviceman were killed by landmine explosions, the official said on condition of anonymity. Rebels also clashed with Russian forces in Grozny four times overnight, wounding two servicemen.

Meanwhile, President Vladimir Putin made his first public statement about Friday's bombing, vowing not to let it stand in the way of efforts to find a political solution to the three-year conflict.

"This was an attempt to disrupt the political process in Chechnya," Putin told his cabinet in televised remarks.

"They can increase the number of victims, including among their own people, but they won't be able to disrupt the process of finding a settlement, and they won't be able to achieve their more sinister goal of disrupting the stabilization of the republic and the strengthening of Russia's statehood as a whole."

Russian officials have repeatedly said the attack was aimed at disrupting plans for a constitutional referendum in March. As an internal Russian republic, Chechnya is entitled to have its own constitution outlining the regional government structure. However, the constitution would be subordinate to Russian law, and there is no talk of giving Chechnya greater autonomy than other Russian regions.

Russian forces continued to hunt for people involved in the bombings. Sixty-four people were detained in security sweeps in Grozny, the law enforcement official said.

Chechen administration chief Akhmad Kadyrov declared three days of mourning, forcing the cancellation of all entertainment including public New Year's celebrations. Workers were quickly constructing temporary buildings for the government in Grozny.

Many officials have said the bombing, at one of the most heavily guarded spots in Chechnya, points to major flaws in the work of the servicemen in charge of security in Grozny.

Chechnya's prime minister, Mikhail Babich, told Channel 1 that charges would be brought Monday against three members of a riot police force that had been guarding the compound. He said prosecutors continued to investigate other officials who may have been negligent.

Sergei Fridinsky, the deputy prosecutor general, said Sunday he was recommending that the city's military commandant and the commandant in charge of guarding the government compound be fired.

Moscow claims international terrorists, teamed with Chechen separatists, were behind the bombings. They also point the finger at Chechen rebel leader Aslan Maskhadov, but a Maskhadov spokesman has denied the rebel leader played any role.

Russian officials have tried to eliminate any lingering foreign support for Maskhadov, who was Chechnya's elected president, by pointing out his alleged links with international terrorists. Col. Ilya Shabalkin, a spokesman for Russian forces in Chechnya, said Monday that authorities had found new evidence of these links in a trove of documents discovered in the village of Gansolchu in the Nozhai-Yurt region of Chechnya, the Interfax news agency reported.

"New evidence proving Maskhadov's orders to prepare and commit large terrorist attacks in the republic, primarily against the local authorities and law enforcement agencies, has been found. There is also evidence of close ties between Maskhadov and gangs operating with international terrorist organizations on Chechen territory," Shabalkin was quoted as saying.

Russian troops left Chechnya in 1996 after a disastrous 20-month campaign against the rebels. They returned in 1999 after rebel raids in a neighbouring region and a series of apartment-house bombings that killed more than 300 people.