(JTA) — More mail bombs like those that were mailed to synagogues in Chicago may be out there, a top U.S. security official told news shows.
John Brennan, the deputy national security adviser, said on the Sunday morning programs that there might be more mail bombs like the two discovered last Friday. He added that the potential attacks are characteristic of al-Qaida in the Arabian Peninsula.
"They are a dangerous group. They are a determined group. They are still at war with us and we are very much at war with them," Brennan told "Meet the Press." "They are going to try to identify vulnerabilities that might exist in the system."
Also Sunday, Yemen security officials released a Sana’a University engineering student who had been arrested after being suspected of mailing the bombs. Hanan Al-Samawi, 22, was released following protests by her fellow students. Police now believe that another woman used Samawi’s name and identity, Reuters reported.
Samawi’s mother, 45, also was arrested, according to reports, but there was no word about whether she was released.
President Obama said last Friday in a televised news conference that the packages headed for the United States constituted a "credible terrorist threat" and had been addressed to Jewish organizations in the Chicago area.
One of the reported targets was Congregation Or Chadash, which serves gay, lesbian, bisexual and transgender Jews, and shares space with Emanuel Congregation, a Reform temple, in a building along Chicago’s lakefront, according to the Chicago Tribune.
A second targeted synagogue reportedly was in Chicago’s East Rogers Park neighborhood, according to the Tribune, though the newspaper reported that no synagogues have been operating in the neighborhood since 2002.
One of the bombs, which was identified and defused last Friday at a FedEx way station in the United Arab Emirates, bore the hallmarks of an al-Qaida bomb, Dubai police said, according to reports. A second, similar bomb was located on the same day in London.
The mail bomb found in Dubai reportedly traveled on two passenger planes to reach the country, Qatar Airways reportedly said Sunday.
Hidden inside printer cartridges, the explosives were large enough to bring down an airplane and could be detonated by remote control.
Brennan said that officials are trying to determine whether the planes or the synagogues were the intended targets.