(CNN) -- Five Hondurans, a Canadian and two U.S. citizens went missing off the coast of Honduras over the weekend, the U.S. Coast Guard said.
Coast Guard and U.S. military aircraft are assisting Honduran rescue teams in the search for the missing boaters.
The boaters set sail from Roatan, Honduras, on Saturday in a 28-foot boat with a 100-horsepower engine, the Coast Guard said in a statement Tuesday.
The boat had been en route to Utila Island in Honduras but never arrived.
Search teams have combed more than 596 square miles since Saturday, the Coast Guard said, but they haven't spotted the vessel.
"We will continue to do whatever we can to try and locate the missing boaters," said Lt. Cmdr. Gabe Somma, a spokesman for the Seventh Coast Guard District.
CNN's Amanda Watts and Catherine E. Shoichet contributed to this report.