GEARHART, Ore. -- Four families coped with unbelievable loss Monday after a plane crashed into a beach house along the Oregon coast, killing five people.

Jason Ketcheson, the pilot, and Frank Toohey, his passenger, worked together and were flying to Klamath Falls on a business trip. Ketcheson's father said he had been a pilot for the last 20 years.

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The pair took off from the Seaside Municipal Airport at about 6:30 a.m. City officials said witnesses reported seeing the plane circling over the ocean and hearing the engine sputtering.

Barbara Miller, who lives in Gearhart, saw the plane when she looked out her window.

"The plane was in the fog and I thought, what is the plane doing so close?" Miller said.

Miller said she immediately assumed something was wrong because the plane was flying so low.

"All of a sudden, it revved its engine and there was a thud, a crash," she said. "Within two seconds … an explosion and then again … another explosion."

The crash and explosions leveled the vacation home. Three people inside managed to escape.

Officials said 8-year-old Grace Masoudi, 12-year-old Hesam Masoudi and 10-year-old Julia Reimann were killed in the crash.

Toohey and Ketcheson were also killed immediately.

The two men worked for Windham Vacation Ownership, which operators a condominium complex in Seaside, as well as several other properties.

Ketcheson leaves behind three kids, while Toohey leaves behind his two sons and his wife of 33 years.

"We're going to miss him and we're praying for the whole family during this hard time," said Mike Stuart, Toohey's friend.

People in the Gearhart community have dropped off flowers at the scene of the crash.

The Federal Aviation Administration will return to the scene Tuesday to comb through the rubble and try to determine what caused the crash.