One of the hijacking suspects who crashed a plane into the Pentagon took intensive English classes and briefly attended flight school in the San Francisco Bay area in 1996.

The FBI has interviewed the family whom Hani Hanjour stayed with that summer, according to Andrew Black, a spokesman with the agency's San Francisco office.

Black said Wednesday that Hanjour lived in the Bay Area from April 30 to early September 1996, when he dropped out of the Sierra Academy of Aeronautics after only half a day.

Federal investigators have concluded that Hanjour re-entered the United States in December 2000 on a student visa after promising to enroll at the same English program, run by ELS Language Centers on the campus of Holy Names College in Oakland.

ELS discovered that Hanjour studied English in Oakland five years ago under the name Hani Hanjoor after the company searched its files for variations on spellings of the hijacking suspects' names. Hanjoor and Hanjour had the same birth date, among other similarities, ELS spokesman Mike Palm said Wednesday.

"I know the FBI is trying to build a timeline, and we're hopeful we've provided a chunk of information," Palm said. "We just provided this file to the FBI a day or two ago."

The ELS sessions involve 30 hours of class time per week, Palm said, and Hanjour's four-month stay was typical.

Black would not identify the family Hanjour stayed with but said the people were not suspects.

Hanjour is one of five men believed to have hijacked American Airlines Flight 77 on Sept. 11 and steered it into the Pentagon. Another hijacked plane, believed headed for a Washington target, crashed in Pennsylvania, and two others destroyed the World Trade Center in New York.

The FBI also learned that Hanjour enrolled at the Sierra Academy of Aeronautics in Oakland, "attended half a day, and then dropped out," Black said.

Apparently, Hanjour was put off by the flight school's rigorous, yearlong course, which at the time cost $35,000.

Hanjour had planned to take the full course, Dan Shaffer, Sierra's vice president for flight operations, told the San Francisco Chronicle. He didn't stay long enough to pay any tuition.

"I think he got scared away," Shaffer told the paper. "This is a strict organization — highly structured and designed primarily for professionals, such as corporate or airline pilots."

Black said Hanjour probably moved on to Arizona, where he apparently received pilot training for three months in 1996 and in December 1997, according to T. Gerald Chilton Jr., a corporate officer for CRM Airline Training Center in Scottsdale.

Hanjour's ties to Arizona date to 1991, when he took an eight-week English course at the University of Arizona's Center for English as a Second Language.

Hanjour apparently used his Bay Area connection again to re-enter the United States late last year.

With a conditional acceptance letter from ELS in hand, he applied from Saudi Arabia for a student visa to enter the program and was supposed to arrive at the school in November, Palm said.

Hanjour never showed up at the school, but a copy of his visa showing that he entered the country in December 2000 was sent by the Immigration and Naturalization Service to the school early this year.

That document went into Hanjour's file in Oakland, and stayed there.

The Princeton, N.J.-based tutoring program never reported Hanjour's absence to the INS.

Schools aren't required to warn the government that foreign students may be in the country illegally, but "most do, as a courtesy," said INS spokeswoman Sharon Rummery.

"Our position is, we were doing everything that the INS asked of us," Palm said. "It's easy to take a step back and look at it in hindsight and be critical."

Palm said about 10 percent of prospective students never arrive for reasons ranging from visa troubles to missed flights.