A Kennewick man walking his dog Tuesday morning saw something unusual flying over the Columbia River.

Around 5:40 a.m., Dan Arrenholz said he saw something odd moving quickly in the sky from the Columbia Center Boulevard area to Pasco near Road 68 and Court Street.

Arrenholz, who works at Hanford, said at first he thought it was an ultralight plane, but it made no sound. And it could have been a parachute, but nobody was dangling from it. Then, as the angle changed, he thought it could have been balloons, but he said it was moving too quickly to be balloons that escaped from a car lot.

"I don't know what it was," he said.

Arrenholz, who was on Arrowhead Avenue, said he was on a route he normally walks in the morning and has never seen something quite like it.

It moved rapidly, diagonally across the river in a steady flight, he said. Arrenholz said he is sure it was manmade.

"It's not like alien visitation or anything like that," he said.

Ron Foraker, Tri-Cities Airport director in Pasco, hadn't heard any reports of something flying of that description Tuesday morning. The Federal Aviation Administration control tower at the airport opens at 6 a.m., after Arrenholz spotted the craft, and Jim Johnson, tower chief, said it wasn't something they had heard of.

The FAA tower doesn't get many calls asking about un-identified flying craft, he said.

The Franklin County Sheriff's Office had not received any reports of an ultralight, balloons or anything unidentified flying in the county, said Undersheriff Kevin Carle.

Neither had the Pasco Police Department.

The National Weather Service in Pendleton doesn't use weather balloons.

The National UFO Reporting Center, which is west of Spokane, did not receive any reports of the object, said director Peter Davenport.

That's not significant, as relatively few people seem to report it when they see one.

The center has nearly 80 reports of UFO sightings from the Tri-Cities, he said.

For example, the center received a report of a bright red light that was high in the sky early Aug. 2 in Kennewick.

On April 11, a Kennewick resident reported seeing three large, white orbs stacked vertically in a formation traveling across the Columbia River.

w Kristi Pihl: 582-1512; kpihl@tricityherald.com