A German has been convicted for firing at houses in Vienna-Hietzing with a slingshot.The 51-year-old was arrested after staff at a doctors practice informed police that the man was damaging the buildings facade last September.The weapon he was using was identified as a high-precision slingshot which has to be registered by owners in Austria. The defendant failed to do so. Policemen discovered several other weapons, none of them licensed, at his flat.The German said in court yesterday (Thurs) he tried to protect a crow from a swarm of other birds when they attacked the fledgling before admitting he was acting out of frustration after being sacked on short notice.The resident of Vienna received a three-month suspended prison term for endangering others and breaching federal weapon laws. The verdict has not yet reached legal status as he asked judges for three days to think over whether to appeal it.Meanwhile, police officers in the Viennese district of Favoriten said they were still investigating an incident in which a kindergarten nurse suffered a bruise on her arm. The woman was hit by a steel bullet most likely fired from an air-powered rifle when she walked home from work last month.