Preliminary information suggested the female driver of a Lada car was driving into oncoming traffic when she hit a truck, before a bus rammed into the two vehicles.
The female driver has been hospitalised, said police, who have opened a probe into the accident.
Six of the injured are in "a serious state," added police.
Russia has one of the highest road accident mortality rates in the world, with almost 28,000 deaths in 2012. Most of the fatal accidents are linked to alcohol usage or a failure to respect road rules.