(Portland, OR) -- A Portland man has been sentenced to two-and-a-half years in federal prison for assaulting an Immigration and Customs Enforcement officer outside of the ICE facility in South Portland. Twenty-five-year-old Robert Hoopes was accused of throwing a rock that hit an ICE agent in the head causing a serious cut over his eye. Hoopes and another person also used a stop sign as a battering ram to damage the entrance to the ICE building. He pleaded guilty to aggravated assault of a federal employee.