At least four people, including three civilians, were killed after Naxals triggered a blast on a bus near Bacheli in Chhattisgarh's Dantewada on Thursday.
The njured personnel of the Central Industrial Security Force have been shifted to a hospital. More details awaited.
The attack has come just days ahead of the first phase of voting for the state assembly elections, in which 18 constituencies, mainly in the Naxal-affected areas, will go to polls.
Just eight days ago, two Chhattisgarh police personnel and a Doordarshan cameraman were killed in a Naxal attack in Aranpur village of Dantewada district.