National Park Service officials said Thursday they are almost certain that no one was on a boat that sank Sunday in about 65 feet of water off Lone Rock Beach on Wahweap Bay at Lake Powell.

A spokeswoman at the district ranger's office said Thursday that park service officials are "99 percent sure that no one was on the boat," which witnesses on shore reported they saw sinking during heavy winds.A district ranger said earlier this week that his office had not received any reports of additional missing boats or information on missing persons. As of Thursday morning, divers still had not entered the water to reach the boat, although a "bleep" was detected on sonar.

"With prevailing winds it is very possible that the boat was blown away from shore," the spokeswoman said. Officials first feared that someone was on the craft when it sank.

About 70 boats were damaged during Memorial Day weekend storms at the lake, and ranger districts throughout the lake have been swamped with calls on damaged boats, people suffering from exposure and many other problems.