The Gulfstream G-1159A jet, coming into Houston, went down about 6:15 a.m. in a wooded area just over three miles south of the airport runway. The former president had been scheduled to travel to Ecuador for a conference.
"I was deeply saddened to learn of the plane crash this morning," said the former president, in a statement released by his spokesman, Tom Frechette. "I'd flown with this group before and know them well. I join in sending heartfelt condolences to each and every member of their families."
"It's very sad," said Frechette, who had planned to accompany Mr. Bush on the trip to Ecuador, along with a Secret Service agent.
The National Transportation Safety Board said the "black box" flight data recorder and the cockpit voice recorder have been recovered, and appear to be in good enough shape to read the data.
Mark Rosenker, the NTSB's vice chairman, said the agency is examining a number of possible factors, including the aircraft's condition, what the pilots were doing, and the weather.
He said standard toxicology tests will be performed on the bodies and FBI agents have joined the investigation at the NTSB's request, as is routine.
"We are treating this at this moment as a transportation accident. We have no reason to believe it is anything other than that," said Rosenker.
Mr. Bush, who lives in Houston, had been planning to give a lecture for the Guayaquil, Ecuador, Chamber of Commerce, a trip that has now been postponed until December.
Authorities say the jet, on its way from Love Field in Dallas, was about three and a quarter miles south of the runway when it clipped the light pole, losing part of a wing.
Rosenker said that the light pole was 120 feet high and that the plane, at that point, should have been at an altitude of 1,000 feet.
Debris from the crash is scattered over an area of over 100 yards.
The crash site is a field near the Beltway 8 tollway. No one on the ground was injured, but one car was hit with debris while another was hit with jet fuel.
Roger Smith, a spokesman for the Houston Airport System, said the pilot didn't indicate any problem, and the landing was routine until communications abruptly stopped. Dense fog blanketed most of the area.
Robert Randall, operations manager with the plane's owner, Jet Place Inc. of Tulsa, Okla., said it had two male pilots and a female flight attendant aboard.