Special forces in Kazakhstan killed four suspected terrorists in a bloody standoff Friday as the Central Asian continues to battle a surge in radical Islamist-related violence. The authorities here said the group was believed to have been involved in a bombing attack on a police station a week ago in the western oil city of Atyrau and appeared to be plotting further assaults. Troops surrounded the group’s hideout in an Atyrau suburb on Thursday. The suspects were killed after they refused to surrender and opened fire on security forces, the General Prosecutor’s Office said in a statement. “Several weapons with ammunition to match, Molotov cocktails, and components for improvised explosive devices were found on the site,” the statement said. Kazakhstan, a sprawling mainly Muslim former Soviet nation west of China, saw a surge last year in terrorist activity apparently linked to Islamist extremism. A number of attacks have been reported over the summer after a largely quiet first half of the year. Dozens have died, mainly suspected terrorists and law enforcement officers, since an unprecedented suicide bombing in May 2011 in the western city of Aktobe. Earlier this month, five people were killed by government troops in in Kulsary, a town around 250 kilometers (150 miles) from Atyrau, after being linked to an explosion at an Atyrau apartment that authorities say was being used to manufacture bombs. There have been similar and possibly related incidents in the more densely populated eastern regions of the country, but the violence has largely been contained to the west. No clear motivation has emerged for the rise of the surge of unrest and signs of religious extremism are unusual for a country in which most Muslims practice a moderate strain of the faith.