Authorities in Yemen have released the female computer engineering student from custody that they suspected of mailing explosive packages, Fox News confirms.

Yemeni authorities concluded this was a case of stolen identity by an individual who knew the detained suspect's name, address and telephone number.

The suspect has been fully cooperating with the investigation, authorities say.

Yemen will not allow the female suspect to leave the country at this time.

A Yemeni government security official tells Fox News that more arrests are likely to come.

"It's not over, and more arrests will take place as early as the next couple of days. We have different suspects in mind and we will further investigate them," the official said.

A spokesman for Qatar Airways said Sunday one of two powerful bombs mailed from Yemen to Chicago-area synagogues traveled on two passenger planes within the Middle East. The U.S. said the plot bears the hallmarks of Al Qaeda's offshoot in Yemen.

The airline spokesman said a package containing explosives hidden in a printer cartridge arrived in Qatar Airways' hub in Doha, Qatar on one of the carrier's flights from the Yemeni capital San'a. It was then shipped on a separate Qatar Airways plane to Dubai in the United Arab Emirates, where it was discovered by authorities late Thursday or early Friday. A second, similar package turned up in England on Friday.

The airline spokesman disclosed the information on condition of anonymity in line with the company's standing policies on conversations with the media. He did not give any timeframe for the two flights in question.

In Washington, President Obama's counterterrorism adviser said Sunday that authorities "have to presume" there might be more potential mail bombs like the ones pulled from planes in England and the United Arab Emirates.

Al Qaeda's offshoot in Yemen is suspected of mailing the bombs. The group was behind a failed bombing on a Detroit-bound airliner last Christmas that bore some of the same hallmarks as this plot.

U.S. officials said suspects in the plot include the bombmaker suspected of designing the explosive used in the failed Christmas airliner bombing. The bombmaker is a key operative in Al Qaeda's offshoot in Yemen, Al Qaeda in the Arabian Peninsula (AQAP).

Authorities were also looking at two language institutions in Yemen the plotters may have been associated with.

The Associated Press contributed to this report.