At least four of the donors were victims of the data-theft scheme, said Jim Williams, a spokesman for the regional agency. An investigation is continuing to determine if any other donors have been affected.

The thefts occurred when a telephone blood-drive recruiter entered random numbers of past donors into her 8,000-donor database, then was able to access the names, Social Security numbers, phone numbers and birth dates of potential victims. The database uses unique donor numbers to store records for each person, and by entering random numbers, the recruiter was able to access the records of the four victims.

The former employee, 20-year-old Lonnetta Shanell Medcalf of St. Louis, then allegedly opened credit card accounts at several stores using the stolen information and made purchases valued at more than US$1,000, according to a statement by the U.S. Attorney's office in the eastern district of Missouri.

Medcalf began working at the Red Cross branch in October and was fired on March 2, when the incidents were discovered, Williams said. Medcalf had 8,000 donor contacts in her database out of more than 1 million donors in the region who were not affected by the data thefts. Her case is scheduled for trial on June 19.

The Red Cross offices in the region last week changed the database software to strictly limit access to any Social Security numbers in the future, Williams said. Only names, phone numbers and birth dates are now accessible by blood drive recruiters.