Dhaka, June 30 -- At least two people were killed Sunday when firefighters tackling a blaze were ambushed by an unknown number of gunmen in an ongoing standoff in the northwestern US state of Idaho, the local sheriff said.

A blaze was still raging on the mountainside in Kootenai County, a popular park and hiking area, as law enforcement exchanged gunfire with the shooter or shooters, Sheriff Robert Norris told reporters.

"We now have two deaths. We have an unknown amount of casualties. We still have civilians that are coming off of that mountain.. We are actively taking sniper fire as we speak," he said at a press conference.

The attack was carried out with high-powered rifles, the sheriff said, stressing that the goal of law enforceme...