By TED MANN

A yacht exploded and sank off the coast of New Jersey on Monday afternoon, leaving 21 passengers, some with unknown injuries, floating in life rafts about 17 miles from shore.
The U.S. Coast Guard received a report of an explosion aboard a vessel named Blind Date at 4:23 p.m., said spokesman Charles Rowe. Everyone aboard apparently made it on to life rafts before the yacht sank.
Nine passengers had been reported as injured, according to a spokesman for the National Park Service, which was helping to organize ambulances waiting to meet the passengers at Sandy Hook, N.J.
The Coast Guard dispatched rescue vessels from stations at Jones Beach, N.Y., and Sandy Hook, as well as helicopters from Atlantic City and Cape Cod. The New York Police Department also dispatched helicopters, a Coast Guard spokesman said.
Little was known Monday evening about the extent of injuries to the passengers, and the cause of the blast wasn't immediately clear.
"Injuries were reported, but we do not know the extent or how many," Mr. Rowe said.