Authorities cancelled an AMBER Alert on Wednesday for 13-year-old Betsabe Perez after she and the man she was with were tracked to an apartment complex in the Fort Worth area with the help of an IP address from a cellphone, Val Verde County Sheriff Joe Frank Martinez said, according to KWTX.

Erik Diaz-Tapia, 19, was arrested, Martinez said.

Perez last seen on September 9 in Del Rio at noon, CrimeOnline previously reported, although the AMBER Alert was not issued until Monday. She was believed to be with Diaz-Tapia.

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The Monitor reported that police believe Perez may be in grave or immediate danger. Whether Perez and Diaz-Tapia know one another remains undisclosed. It’s also unclear what prompted authorities to issue an AMBER Alert nearly a month after Perez’s disappearance.

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[Featured image: Betsabe Perez, Erik Diaz-Tapia/Texas Department of Public Safety]