HARVEY, Ill. (CBS) — Olivia Cobbins was hired to crack down on police corruption in Harvey – but only after a few months on the job, she resigned in disgust.

Cobbins talked exclusively Wednesday to CBS 2 Political Investigator Dana Kozlov about what she claims is rampant, ongoing misconduct in the south suburb.

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“My passion is police reform,” Cobbins said.

And that passion is why Cobbins said she signed on in August as the head of internal affairs for the Harvey Police Department. The former Chicago Police officer said she had Mayor Christopher Clark’s blessing to clean up misconduct.

But this week, with less than three months on the job, Cobbins handed in her letter of resignation.

“I couldn’t stand – in the position that I was in, as a woman, and as a police officer – and see the level of corruption and misconduct in Harvey,” Cobbins said. “I couldn’t stay.”

In her letter, Cobbins focuses on an incident at Thornton Township High School in October. She said an officer came to her with allegations that Harvey’s deputy chief punched a handcuffed student in the chest.

Cobbins said when she tried to investigate, police higher-ups blocked her from accessing evidence – including body cam video.

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“And it wasn’t the first time,” Cobbins said. “This was more like the third time that my access was restricted.”

She also said a higher-up laughed at her attempts to look into death threats against a Harvey officer.

“When his cries for help were laughed at, I knew I couldn’t stay,” Cobbins said.

Clark beat longtime Harvey Mayor Eric Kellogg in the 2019 race – promising to crack down on violence and police corruption. But Cobbins said in her opinion, nothing is improving.

“If I don’t stand up for the people that live in Harvey, no one will,” she said.

We called and visited the Harvey Police Department and City Hall. The mayor did not make himself available.

But in a statement, City Administrator Timothy Williams called Cobbins’ claims “vengeful utterances” from an ex-employee who had been “facing termination” – and called the charges that her superiors had impeded her investigation “blatant lies.”

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But Cobbins called the City of Harvey’s reply blatantly untrue. She said she has reached out to both the Department of Justice and the FBI to report her concerns.