SAN ANTONIO – A reigning Teacher of the Year at a Texas elementary school abruptly resigned last Friday amid an investigation into her ties with a suspected killer.

Southwest Elementary School kindergarten teacher Violeta Rodriguez resigned Friday during a district investigation into her “affiliation with a recent incident that resulted in the death of an individual,” KENS 5 reports.

During Rodriguez’ time at Southwest Elementary she was visited regularly by Ignacio Ruiz, who was paroled in 2013 for the attempted murder of a police officer more than 20 years earlier. Police believe Ruiz, 38, used Rodriguez’ car in the commission of another murder in Bexar County on New Year’s Day, and Rodriguez was suspended with pay from the school district in January, according to the news site.

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School officials said Rodriguez passed a background check in order to visit Rodriguez – which consisted of a driver’s license scan and running his name through the sex offender registry – just months after his release from prison.

“Nobody called the principal, nobody called central office to let us know or make us aware of the situation, but had we known any further information we would have definitely taken the actions necessary,” Southwest Independent School District Spokeswoman Andriana Garcia said.

“Multiple employees of Southwest Elementary School told KENS 5 Ruiz repeatedly visited Rodriguez last semester, but rarely if ever checked in at the front office,” according to the news site.

District officials said most of Ruiz’ visits were after school hours.

Police believe Ruiz shot two men at a home on Macdona Lacoste Road New Years Day, killing Joshua Vidales, 27, before abandoning Rodriguez’ vehicle and stealing another to flee to Piedras Negras, Mexico. There he allegedly shot four people the next day, killing a police officer and cab driver, KENS 5 reports.

Rodriguez taught kindergarten, bilingual studies and fourth grade at Southwest Elementary since joining the staff in 2007. Police believe she developed a relationship with Ruiz.

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Ruiz was eventually apprehended in Mexico, where he will stand trial for the murder of the police officer and cab driver. Local law enforcement officials told KENS 5 Ruiz will be punished for those crimes in Mexico before any extradition to the United States.

Charges were not expected against Rodriguez and it’s unclear why she resigned.

Ruiz’ initial prison sentenced stemmed from an incident in April 1993 when the then 16-year-old allegedly fired a shotgun several times at a San Antonia Police officer, though Ruiz missed and the officer took him down with a shot to his lower body, according to the news site.

He was charged as an adult.