WASHINGTON (AP) -- A union leader says hackers broke into the Federal Aviation Administration's computer system last week, accessing the names and Social Security numbers of 45,000 employees and retirees.

Tom Waters, president of American Federation of State, County and Municipal Employees Local 3290, said FAA officials briefed union leaders Monday about the security breech.

FAA spokeswoman Laura Brown confirmed that the agency's computers were hacked last week.

Waters said union leaders were told hackers gained access to two files. One file had the names and Social Security numbers of 45,000 employees and retirees on FAA's rolls as of February 2006.

He said the other file contained medical information that was encrypted.

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