VLADIKAVKAZ - Ten Russian servicemen were killed and 11 were wounded in rebel attacks across Chechnya over the past 24 hours, an official in the pro-Russian Chechen administration said Tuesday.

One of the soldiers was killed and one wounded during an hour-long shootout with rebels in the town of Argun, 15 kilometers (9 miles) east of the capital Grozny, said the official, who spoke on condition of anonymity. Two rebels' bodies were found after the clash, he said.

Argun, where large numbers of hard-line Islamic militants are believed to be based, is one of the most restive towns in Chechnya, with frequent land mine explosions and continual security sweeps by Russian troops.

Three soldiers were killed and three wounded in two separate mine attacks against Russian military trucks, one in Grozny and the other in the village of Yalkhoy-Mokhk in the eastern Kurchaloi region. Rebels opened fire on a Russian armored troop transporter, killing two servicemen and wounding one. And militants staged hit-and-run attacks on 26 federal posts, killing four and wounding seven, the official said.

More than 90 people were detained across Chechnya over the past 24 hours for suspected ties with rebels, he said. Troops sealed off approaches to the towns of Kurchaloi, in the east, and Shali, in the south, for intensive searches, while they continued a weeklong series of house searches in the northern town of Gudermes.

The searches there followed the recent killings of two Chechen police officers and a firefighter by masked men who broke into their houses overnight.

Another round of searches began Tuesday in the vicinity of Grozny University, the Interfax news agency reported. It said that armored vehicles were parked all around the university perimeter and that classes had been canceled out of concern for students' safety.

Rebels pushed Russian forces out of Chechnya in 1996, after a 20-month war that brought the region de facto independence. Russian troops returned in fall 1999, after Chechnya-based rebels raided a neighboring Russian region and after a series of apartment house explosions that killed some 300 people. Russian authorities blamed Chechen rebels for the blasts.