A gunman in Austria killed four people, including three police officers, and fired sporadically at police after barricading himself in a farm building, officials said.
After a 12-hour standoff, police stormed the building with body armor and assault weapons and were searching for the suspect, Interior Ministry spokesman Karl-Heinz Grundboeck told The Associated Press. It wasn't immediately clear whether he was still in the building and the search was widening to other nearby buildings on the farm grounds.
The hunt stretched on more than three hours. Grundboeck said police were moving carefully in an area with many possible hideouts and locked doors. "The safety of our police is our top priority," he said, shortly before midnight.
The killings began about 24 hours earlier, when police stopped the man on a road near a wilderness area west of Vienna where there has been frequent poaching.
Austrian media said the man was a suspected poacher. Police named the suspect as Alois Huber, a 55-year-old businessman.
The gunman fled in his car, which landed in a ditch in the nearby town of Annaberg, then shot and wounded a member of Austria's Cobra SWAT team at a police checkpoint, said Grundboeck.
The police officer later died.
An ambulance raced to the scene, but the gunman shot and killed its driver as he tried to give first aid to the wounded policeman. The gunman also shot and wounded another officer at the scene.
Later Tuesday, another officer who had been missing was found shot dead in his patrol car, said Grundboeck. Regional police spokesman Roland Scherscher said that officer was apparently killed after the suspect carjacked the police vehicle and took him hostage.
The attacker then fatally shot another police officer at a roadblock before barricading himself in the farm building on the outskirts of Melk, a central town 70 kilometres west of Vienna, Grundboeck said.
The gunman sporadically fired at police units near the building, with the last shot heard about an hour before police piled into three Austrian army tanks and moved in.
Scherscher said he could not confirm an Austrian media report that the suspect was shot in the abdomen by police before he sought refuge inside the farm building.
The provincial government of Lower Austria ordered black flags flown from all public buildings in honor of the gunman's victims.