An al-Qaida commander is saying Osama bin Laden's terrorist network is responsible for last month's attack on a Tunisian synagogue. The claim occurs as U.S. authorities warn of a possible major attack against the United States.

On April 11, a man driving a truck containing cooking gas crashed into a wall at the historic El Ghirba synagogue on the Tunisian resort island of Djerba. Nineteen people were killed, including 11 German tourists.

Initially, the Tunisian government said it was a tragic accident. But weeks later, German Interior Minister Otto Schily said investigators were sure it was a terrorist attack. German officials said they had evidence linking the attack to al-Qaida.

Now, a man identified as an al-Qaida leader has claimed the terrorist network is responsible for the attack.

The London-based pan-Arab newspaper Asharq al-Awsat said it interviewed Abdel Azeem al-Muhajir, whom it described as a "senior military leader" of al-Qaida, in Pakistan's mountains near the border with Afghanistan. The newspaper quoted the al-Qaida commander as saying the attack was carried out by "brothers in the al-Qaida network."

Mr. al-Muhajir also told the newspaper that in the near future Americans would suffer "a more painful hit" than the Tunisian attack.

He said al-Qaida has not been destroyed by the U.S.-led war on terrorism, and said Taleban fighters have come a long way in their training for a "soon expected fight with appropriate arms." He did not specify what kinds of weapons might be used.

Meanwhile, the FBI says it has information that al-Qaida members may be planning bomb attacks at apartment buildings in U.S. cities. An FBI spokeswoman said the information is "unspecific" and "uncorroborated," but was released as a precaution.

U.S. intelligence officials say recently monitored communications among militants of the al-Qaida network indicates preparations may be under way for another major attack. An assault could be made in the United States or on American interests in Europe or the Arabian Peninsula.

The New York Times is reporting that recent intercepted messages appear similar to those picked up a year ago, before the September 11 attacks on New York City and Washington. The newspaper reports U.S. authorities say the messages do not reveal the timing, location or method of attack.