A 67-year-old man was killed andsix people were injured on Sunday afternoon when their mini- bus collided with a private bus on Mumbai-Pune Highway, Navi Mumbai police said.The deceased, identified as Kamarali Islam, and the six injured men were on their way to Ahmedabad in Gujarat from Shimoga in Karnataka, an official said."The injured have been admitted in MGM Hospital in Kamothe. Driver Vagesha Ramchandrapa was arrested for rash driving and causing death by negligence," he added.