Pope Francis has come under scathing criticism from a growing number of traditionalist Catholics for cracking down on a religious order that celebrates the old Latin Mass.

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The matter concerns the Franciscan Friars of the Immaculate, a small but growing order that was founded in Italy in 1990 as an offshoot of the larger Franciscan order of the Pope's namesake, St. Francis of Assisi.

The Vatican in July took the order over and last week imposed remarkable sanctions: closing its seminary, suspending ordinations, and requiring priests to accept the post-Vatican II Mass.

The case has become a flashpoint in the ideological tug-of-war going on in the church over Francis' revolutionary agenda, which has thrilled progressives and alarmed conservatives.