Eight soldiers and four Islamic extremists have been killed in the last few days in eastern Algeria, security officials said Saturday.Six of the soldiers were killed while conducting an operation to sweep out extremists near Tebessa, they said. A seventh was targeted in an attack outside a mosque near Dellys. The eighth soldier was killed in an operation in mountains above Tidjellabine. Three armed Islamists also died. The fourth Islamist, a regional leader who was trying to seize an army camp in Skikda, was also killed.