A Mexico native serving time in a prison south of the border for rape had his naturalized U.S. citizenship revoked by a federal judge Tuesday after authorities discovered the man failed to disclose a previous child sex assault conviction dating back more than 20 years.

The decision to denaturalize Jose Arizmendi, 54, made him the 88th person in the last eight years to have his citizenship revoked, according to a review by SeattlePI.com. Arizmendi had been living in Texas, making him the ninth person from the Lone Star State in eight years to be denaturalized.

“The Justice Department is committed to preserving the integrity of our nation’s immigration system,” Acting Assistant Attorney General Chad A. Readler said in a statement. “We will aggressively pursue denaturalization in cases where individuals lie on their naturalization applications, especially in a circumstance like this one, which involved a child sex abuser. Civil denaturalization cases are an important law enforcement tool for protecting the public, including our children.”

Arizmendi, who is currently serving an 18-year sentence in Mexico for the rape of a minor there, did not tell officials at his immigration interview in October 1995 about his conviction six months earlier for the aggravated sexual assault of a child, according to a Department of Justice news release. Arizmendi was given 10 years of probation in that case, The Houston Chronicle reported.

When officials approving his immigration request asked if he had ever been arrested or convicted of a crime, Arizmendi told them: “No.”

Partly based on that answer, Arizmendi became a U.S. citizen in 1996. But immigration officials eventually uncovered the child sex assault conviction and alerted the DOJ, which initiated proceedings to strip Arizmendi of his citizenship in February 2015.

Because of a 10-year statute of limitations, U.S. authorities couldn’t revoke the citizenship based on the criminal conviction alone – but due to Arizmendi’s lie to immigration officials, they were able to strip it as a civil denaturalization.

“Applications for naturalization must be candid with all material facts,” Acting U.S. Attorney for the Southern District of Texas Abe Martinez said in a statement. “Like in this case, failing to disclose material data should result in denaturalization.”