Two people were killed in separate traffic accidents in Chatham and Andover Saturday evening. On the Cape, police said a driver refused to stop for police in Harwich and fled into Chatham along Route 28, leading to a multi-vehicle crash near 1653 Main St. in Chatham around 6:20 p.m. Chatham police, who did not identify the person killed, said criminal charges will be filed against the driver. Separately, a 46-year-old Methuen man died after a single-vehicle accident on Route 125 South in Andover, State Police said. The man, who was not identified pending family notification, was driving alone in a Chevrolet Astro van just before 6:30 p.m. when the van veered off the roadway and into a wooded area where it struck a large tree, Trooper Todd Nolan said. The cause of the crash is under investigation by state troopers, Nolan said.