PITTSBURGH — A Valencia woman who owns a horse rescue organization is facing more federal charges after a grand jury indicted her Monday for mail fraud.

Pamela A. Vivirito, 46, of 372 Steiner Bridge Road, is the sole defendant in a seven-count indictment filed Monday in Pittsburgh. She is charged with two counts of extortion and five counts of mail fraud. The extortion charges were filed by federal prosecutors last year.

A grand jury alleges that Vivirito extorted two people — identified in court documents as “Person 1” and “Person 2” — by threatening to expose sexual affairs she allegedly conducted with them.

Court documents say the first victim, which Vivirito alleged extorted over a three-year period, from May 2012 to March 2015, was the owner of commercial rental properties and ran a construction business. The second victim is referred to only as a business owner. A Department of Justice spokesman said Tuesday that the office could not release more specific information on the alleged extortion scheme.

The mail fraud charges added on Monday claim that, starting in January of 2011, Vivirito used her horse rescue organization, Equine Angels Rescue, to defraud donors of more than $18,000, which she then used for personal expenses. According to the indictment, donors from New York, Delaware and Pennsylvania were defrauded by the scheme, which lasted from 2011 into late 2013.

If convicted on the charges, Vivirito faces a total sentence of 140 years in prison and a fine of $1.75 million.