One of the judges, Mustafa Yucel Ozbilgin, was shot in the head and died later in hospital, the Anatolia news agency reported.
Four of the judges - including Ozbilgin - had voted in February against the promotion of an elementary school teacher who wore an Islamic-style head scarf outside of work. The fifth had voted in favor.
The judges' pictures were published by the pro-Islamic Vakit newspaper.
The attacker, who was detained and was being interrogated by anti-terrorism police, shouted "I am the soldier of God," before opening fire. He said carried out the attack to punish the judges for their decision on headscarves, said Tansel Colasan, deputy head of the administrative court, the Council of State.
The head of the court chamber, Mustafa Birden, was wounded in the liver and the spleen and was successfully operated on, Prof. Dr. Ugur Erdener of Hacettepe University Hospital said. A sixth judge escaped the attack unharmed by throwing himself onto the floor, reports said.
Birden reportedly had received death threats, and the administrative court complained recently that its members could become targets, private CNN-Turk TV said. The TV station reported that the attacker, a lawyer, was being monitored by police for alleged ties to the radical Turkish Islamic group of Hezbollah. The group bears the same name as the better known Lebanese group, but is unrelated.
The attack stoked tension between the secular establishment and Prime Minister Recep Tayyip Erdogan's Islamic-rooted government, which had strongly criticized the court's headscarf decision in February, the AP reports.
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