Developers reproduce crashes to understand root causes during software debugging. To reduce the manual effort by developers, automatic methods of crash reproduction generate new test cases for triggering crashes. However, due to the complex program structures, it is challenging to generate a test case to cover a specific program path. In this paper, we propose an approach to automatic crash reproduction via test case mutation, which updates existing test cases to trigger crashes rather than creating new test cases from scratch. This approach leverages major structures and objects in existing test cases and increases the chance of executing the specific path. Our preliminary result on 12 crashes in Apache Commons Collections shows that 7 crashes are reproduced by our approach of test case mutation.