A former social worker and three employees of a residential-care facility for the disabled have been charged with selling the identities of children in their care to help others cheat on their taxes - a scheme U.S. Attorney Zane David Memeger described Thursday as "truly despicable."

Federal prosecutors unsealed an indictment accusing Gebah Kamara, 46, of Sharon Hill, of stealing personal information from several foster children he encountered while working for Catholic Social Services, the charitable wing of the Archdiocese of Philadelphia.

Also charged were Musa Turay, 41; Ibrahim Kamara, 48; and Foday Mansaray, 38 - all employees of the Villanova-based Devereux Foundation, a charity that runs residential centers for patients with developmental disabilities. The three also held jobs at Medmans Financial Services, a Southwest Philadelphia tax-preparation firm.

IRS investigators say that company's owner, Mohamed Mansaray, paid Gebah Kamara and the others for the stolen Social Security numbers and other information, and then charged his clients $800 to claim the children as fraudulent dependents on their tax returns.

In addition to Mansaray and the three who worked for Devereux, two other employees of Medmans were also charged with counts of conspiracy, tax fraud, and identity theft.

Momolu Sirleaf, owner of a separate tax-preparation service in Darby Borough, also faces charges for a similar scheme involving identification information of foster children.

In all, prosecutors claim the purported fraud bilked the government out of at least $6 million in unpaid taxes from 2008 to 2013. Five of the eight defendants were arrested Thursday and made initial appearances in federal court in Philadelphia. All were released on bond after surrendering passports from West African nations such as Liberia and Sierra Leone.

Few had attorneys. Gebah Kamara and his lawyer, James Polyak, declined to comment about the case.

Representatives from Catholic Social Services did not return calls Thursday for comment. Gebah Kamara left the agency in 2011 for reasons unrelated to his arrest, Polyak said.

It remained unclear whether Devereux, whose spokeswoman also did not return calls, still employed Turay, Mansaray, and Ibrahim Kamara. It was unclear whether the two Kamaras and the two Mansarays were related.

If convicted, each of the eight defendants faces possible decades-long prison terms.