Four passengers and the pilot have been killed after their small plane crashed into the sea shortly after take-off from an airport in Honduras.<br />Local authorities say Saturday evening's crash happened off Roatan island, a tourist destination on the county's Atlantic coast.<br />It's still unclear what caused the plane to crash.<br />All of the passengers were U.S. citizens.<br />The plane was headed to the tourist port city of Trujillo, about 80 kilometers from Roatan. <br />
