Russian President Vladimir Putin made an unannounced visit to Chechnya on Sunday, laying flowers at the grave of the war-ravaged region's assassinated president a week before a vote to replace him. Putin arrived early in the morning in slain Chechen President Akhmad Kadyrov's home village of Tsentoroi, Russian news agencies reported. He placed flowers at Kadyrov's grave along with Kadyrov's son and the Kremlin's favored candidate in the Aug. 29 election, regional Interior Minister Alu Alkhanov, the reports said. Putin's visit came after a night of heavy fighting in the Chechen capital Grozny, where authorities said rebels attacked a police station near a central square as well a police patrols and a polling station for next week's vote. Accounts of casualties varied. The fighting at the police station left seven police and nine civilians dead, an official in Chechnya's Moscow-backed government said. The official, who spoke on condition of anonymity, said more than 10 other bodies had been found but not yet identified. Three police were killed and six wounded in attacks on patrols in Grozny, the official said, and one polling place in the capital came under fire from a grenade launcher. A duty officer at Chechnya's Interior Ministry said that one policeman had been killed and another taken captive by the attackers, and that an attack on a Grozny school injured two firefighters who were acting as guards. A spokesman for Russia's military campaign in Chechnya, Maj. Gen. Ilya Shabalkin, said some 50 militants were killed, the ITAR-Tass and Interfax news agencies reported. ITAR-Tass initially quoted Shabalkin as saying 16 civilians were killed, but later he said they were injured.