Initial laboratory testing by the FBI turned up no evidence of explosive materials in the bottles carried at Tri-State Airport in West Virginia by Rima Qayyum, a 28-year-old Pakistani woman dressed in the traditional Islamic headcover.

No charges were filed against the woman, who was never detained and was cooperative when interviewed by the FBI.

Qayyum's mother, Mian Qayyum of Jackson, Michigan, told The Associated Press that her daughter is four months pregnant, lives in Barboursville and is innocent.

"It was not only a false alarm, it was racial discrimination because there was nothing," Mian Qayyum said. "They should clear her name and apologize on national TV."

The FBI did not return messages Thursday night seeking comment on the allegations.

A screener noticed a bottle in Rima Qayyum's carry-on bag as she was going through security before her 9:15 a.m. flight Thursday to Charlotte, North Carolina, airport authority president Jim Booton said.

The terminal was evacuated at 11:25 a.m. after two bottles of liquid in the bag initially tested positive for explosives residue twice, and a canine team also got a positive hit. Chemical tests of the bottles' contents later turned up no explosives, said Capt. Jack Chambers, head of the State Police Special Operations unit.

The woman had purchased a one-way ticket to Detroit by way of Charlotte on Wednesday. The flight eventually left for Charlotte without her.

Rima Qayyum planned to return to the airport Friday to take another flight, her mother said.

"She just had water to drink because she is pregnant and she had a face wash that had a drop of bleach on it," Mian Qayyum said.

The FBI plans to perform additional tests on the bottles Friday, Killeen said.

U.S. authorities banned the carrying of liquids onto flights last week after British officials made arrests in an alleged plot to blow up U.S.-bound planes using explosives disguised as drinks and other common products.

The TSA screening looks for a range of explosives residue, some of which can be found on common household items, said TSA spokesman Darrin Kayser.

"Anytime a prohibited item is brought to a checkpoint, then you are going to be immediately more interested in that bag," Kayser said.

Two airlines - Comair and US Airways Express serve the airport. Commercial airline service was suspended, and about 100 passengers and airport employees were ordered to leave the terminal, Booton said.

After the evacuation, many passengers decided to stay and wait it out.

"We bought them pizza, soft drinks ... tried to make them comfortable as could be in this situation," said Larry Salyers, the airport's manager. "We had them in the parking lot, under trees, in conference rooms, the firehouse."