The head of Ukraine’s police patrol, Yevhen Zhukov, has handed in his resignation after two police officers were seen fleeing the scene when a gunman opened fire in Kyiv, killing at least six.“As an officer with combat experience, I have decided to tender my resignation from my current post. I believe this is the right thing to do,” said the police general at a press conference in Kyiv on Sunday.It comes after an unknown gunman killed at least six people and injured more than a dozen others in...