NEW YORK (Reuters) - Authorities in Massachusetts have identified five Arab men as suspects in Tuesday's attack on New York City and have seized a rental car containing Arabic-language flight training manuals at Logan International Airport, a source told the Boston Herald newspaper.

Two of the men were brothers whose passports were traced to the United Arab Emirates, the unidentified source told the Herald. One of the men was a trained pilot, the paper reported on its Web site on Wednesday.

The paper said investigators suspect the two brothers were aboard hijacked United Airlines flight 175, which pilot union officials said was one of the aircraft that crashed into the World Trade Center.

Flight UA 175 left from Boston en route to Los Angeles with 56 passengers on board. American Airlines flight 11 from Boston to Los Angeles crashed into the other World Trade Center tower. Another aircraft hit the Pentagon and a fourth aircraft crashed in Pennsylvania.

At least two other suspects flew to Logan on Tuesday from Portland, Maine, where authorities believe they had traveled after crossing over from Canada recently, the Herald reported.

Authorities were informed about the rental car by a civilian who got into a fight with several Arab men as they were parking their car, the paper reported.