Which of the following was NOT attacked before the crash of the helicopter? [br]

A U．S．Apache attack helicopter crashed Monday north of Baghdad，killing both pilots，a day after a series of suicide attacks left nearly three dozen people dead in northern Iraq.
     The AH-64 crashed in Mishahda, 20 miles north of the capital, and was in flames on the ground. Heavy gunfire was heard at the time of the crash and shots also were heard afterward, a witness said.
     The attack came hours after three suicide bombers struck a police headquarters, an army base and a hospital around Mosul on Sunday, killing 33 people in a setback to rebuilding the northern city’s police force. The group al-Qaida in Iraq, headed by Abu Musab al-Zarqawi, claimed responsibility for the attacks in Iraq’s third-largest city. The relentless carnage has killed at least 1,338 people since April 28, when Prime Minister Ibrahim al-Jaafari announced his Shiite-dominated government.