A 67-year-old East Boston man died after being hit by a vehicle while walking on Land Boulevard in Cambridge early Wednesday, authorities said. Conrado Medina was taken to Massachusetts General Hospital, where he was pronounced dead, State Police spokesman David Procopio said. The crash occurred at 5:12 a.m. at 40 Land Boulevard, near the Royal Sonesta Hotel, Procopio said. The driver was not hurt in the accident. The driver, a 40-year-old Cambridge man in a 2006 Hyundai Sonata, remained at the scene, State Police said. The crash is under investigation by State Police.