(AP) – Church officials say a pair of nuns embezzled a “substantial” amount of money from the Southern California Catholic school where they worked for decades and used it to pay for gambling trips to Las Vegas casinos.

Adrian Alarcon, a spokeswoman for the Archdiocese of Los Angeles, said Monday the embezzlement appears to have gone on for about 10 years.

During that time Sister Mary Margaret Kreuper was principal of Saint James Catholic School in Redondo Beach. Sister Lana Chang taught eighth grade there. Both retired earlier this year.

The nuns belong to the Sisters of St. Joseph of Carondelet, which says both nuns have apologized and promised to make restitution.

Alarcon says the exact amount involved is still being tabulated.

The archdiocese has reported the situation to police. An investigation is ongoing. No charges have been filed.