Insurgent attack on Afghan police station kills 3 June 19, 2012 -- Updated 0916 GMT (1716 HKT) The attackers disguise themselves as police officers to mount the attack All four insurgents die in the ensuing gun battle in Kandahar A mine explosion a day earlier kills eight civilians in Helmand Kabul, Afghanistan (CNN) -- Insurgents in disguise attacked a police station in the southern Afghan city of Kandahar on Tuesday, killing three police officers and wounding seven others, the local authorities said. The four insurgents wearing police uniforms tried to enter the building at 6 a.m. local time, but police officers confronted them and a gun battle ensued, according to the office of the Kandahar governor. All four attackers, who were armed with light weapons and hand grenades, were killed, the governor's office said. The day before, a mine exploded near a civilian vehicle in the southern area of Helmand Province. The blast killed eight people and wounded five others, according to the Afghan Interior Ministry. The authorities said the mine had been planted by militants seeking to undermine "peace and stability."