Thousands of people held a demonstration in the streets of the rich Siberian oil town of Nefteyugansk on Friday to protest the killing of the town's mayor.


Vladimir Petukhov, 48, was walking to work Friday morning when he was shot in the head and chest by an unidentified assailant, his aides said in a telephone interview. He died three hours later. His bodyguard was also shot and remains in serious condition in a local hospital.


But police, who are treating the death as a contract killing, have obtained a description of the killer from the bodyguard and another eyewitness, ORT television reported. Police have detained two suspects, who boarded a flight out of nearby Surgut on Friday evening, television reported.


"People are in a state of very intense anger," Yulia Korshakeyevich, Petukhov's aide, said in a telephone interview from Nefteyugansk on Friday. "He was a very decent man."


Korshakeyevich said crowds had blocked a bridge and federal roads to protest Petukhov's murder. Even through the telephone, cheers could be heard from the crowd outside the Mayor's Office. A voice called on the crowd to stage a general strike.


Citing local observers, ORT reported that police thought the death may have been a matter of personal revenge or it may have been linked to Petukhov's business activities.


After he was elected mayor in 1996, Petukhov's wife took over his businesses, which included an oil services company. ORT said he had closed down one of the town's two public markets, leaving his wife in control of the only remaining one.


ORT said a check by the audit chamber had uncovered misappropriation of budget funds in Petukhov's administration. A commission from Moscow was about to investigate the use of the town's budget funds, television reported.


Petukhov was also involved in a public dispute with the Yukos oil company, which controls all the wells around Nefteyugansk and provides 90 percent of the taxes for the town's budget.


Last month, Petukhov led a protest that disrupted a meeting of Yukos shareholders. Blaming the company for wage arrears to municipal workers, the mayor called on Yukos to pay taxes that he said it owed.


Petukhov had also approached President Boris Yeltsin and other top officials in Moscow asking for an investigation into Yukos tax payments. Another of Petukhov's demands had been the resignation of two local police chiefs, who he accused of helping Yukos.


Natalya Mandrova, a spokeswoman for Yukos, said Friday that the company was "shocked" by Petukhov's murder.


"We are extremely interested in maintaining stability in the region," she said.


She said Yukos had in fact paid more in taxes than was required by law. She said Petukhov was complaining because taxes this year were lower than last year. But she said this was a result of the fall in world oil prices.


She said Nefteyugansk's local budget in 1997 was 1.5 billion old rubles ($258,000), which was four to five times that of Moscow on a per capita basis.


Mandrova said Yukos had asked the presidential administration and the prosecutor general to inquire into the city's finances.