The Bishop of Würzburg said he had been left "speechless" by the axe attack on a train the city on Monday. Three people from Hong Kong were seriously hurt and another was slightly injured in the axe and knife attack by a 17-year-old Afghan refugee, who was subsequently shot dead by police. A further 14 people were treated for shock. ISIS has claimed responsibility for the attack, with the claim posted on the group's Aamaq news agency on Tuesday. The news agency described the teenager as an ISIS "fighter" who "carried out the operation in answer to the calls to target the countries of the coalition fighting the Islamic State". It has been reported that the teenager shouted "Allahu akbar" ("God is great") and that an ISIS flag was found in his room. A statement was released on behalf of Bishop Friedhelm Hofmann in which he said, "One is speechless at such a moment. This fact can not be understood." In the statement, the bishop said he would pray for all those injured and affected by the attack. "I especially want to thank all those who have intervened in this difficult situation yesterday and helped, including the police and the rescue services," he added. Bishop Hofmann warned against placing all asylum seekers under general suspicion of carrying out attacks. "Maybe we need to help the unaccompanied young refugees even more and help them to overcome their own traumas," he said.