Canadian Armed Forces Station in Afghanistan

Afghan officials say eight civilians and four policemen have died in two separate roadside bombings in Afghanistan.

Authorities say the civilians were killed Tuesday when a bomb hit their bus in the Delaram district of Farah province.

The western province borders Iran and is a common target for insurgents fighting Afghan soldiers and their Western allies.

Officials say the four Afghan policemen were killed in Logar province, south of Kabul, when a roadside bomb hit their vehicle today.

Also in Logar, hundreds of protesters blocked a highway after foreign troops killed a religious teacher in an overnight raid.

In the southern province of Helmand, U.S.-led forces say they killed several militants during an operation to stop weapons smugglers in Garmser district.

Tens of thousands of foreign forces have been helping Afghan soldiers battle insurgents and rebuild Afghanistan since the U.S.-led coalition pushed the Taliban government from power in 2001.