"It certainly showed how incompetent the INS is," Rep. James Sensenbrenner, R-Wis., said on CBS' The Early Show. "It is one fiasco after the other."

The INS action also got the attention of President Bush, who on Wednesday spelled out his displeasure on learning that student visas for Mohamed Atta and Marwan Al-Shehhi were delivered six months after they flew hijacked jetliners into the World Trade Center.

Bush ordered the attorney general to investigate and press the INS to do better. "They got the message and hopefully, they'll reform as quickly as possible," Bush said at a news conference.

The president first said he was "stunned, and not happy" when he learned about the visas. "Let me put it another way: I was plenty hot," he added.

Bush said he was unhappy that the visas remained in the immigration pipeline even though the names on the forms were widely known. He said INS Commissioner James Ziglar was responsible for "this embarrassing disclosure," but should be given a chance to rectify the problem.

"His responsibility is to reform the INS; let's give him time to do so. He hasn't been there that long," Bush said.

Sensenbrenner is proposing to replace the INS with two separate agencies that would be under the control of an assistant attorney general. He said Ziglar does not have the proper managerial background to run either agency.

"Mr. Ziglar should lead, follow or get out of the way," the congressman said.

On Monday, six months after the attacks, Huffman Aviation in Venice, Fla., received student visa approval forms for Atta, 33, and Al-Shehhi, 23. The men were aboard separate hijacked planes that struck the World Trade Center towers, killing thousands.

The pair trained at Huffman in 2000 and early 2001 and sought student visas so they could attend technical schools. The visa for Atta, of Egypt, was approved in July 2001 and a visa for Al-Shehhi, of United Arab Emirates, was approved the following month, said Russ Bergeron, an immigration agency spokesman.

Bergeron described the paperwork the flight school received as a backstop on notification the INS gave the men and the school last summer. He said the INS had no information "regarding these people and their link to terrorism" when the visas were granted.

Rep. Mark Foley, R-Fla., whose district borders the flight school, said the INS can't blame a lack of funds or equipment.

"How this wasn't discovered by even a rank-and-file worker is beyond my comprehension," Foley said. "Anything with Mohamed Atta's name on it should send alarm bells blasting."