A husband and wife who were U.S. Customs and Border Protection officers in South Texas have been sentenced in a marriage and citizenship scam.

A federal judge in Del Rio on Thursday sentenced 46-year-old Isabel Metzler to six months in prison. Officials say 37-year-old Luis Morales received five years' probation.

Metzler pleaded guilty to conspiracy to commit marriage fraud. Morales pleaded guilty to making a false statement to a federal agent.

Prosecutors say the couple arranged a sham marriage for a friend — a British citizen and former city of Austin employee, Nancy Chan — to a man they knew. Chan and the American wed in 2011, then in 2014 sought naturalization for her.

Chan was convicted of fraud-related counts and was sentenced last summer to one year in prison.