Donald Trump’s campaign manager Corey Lewandowski was charged today with battery of former Breitbart reporter Michelle Fields during a March 8 incident at the Trump National Golf Club in Jupiter, Florida, police said.

Lewandowski was charged with one count of simple battery, a misdemeanor, by the Jupiter Police Department.

“Lewandowski then grabbed Fields’ left arm with his right hand, causing her to turn and step back,” according to the police report, describing new video of the incident. “Based on the above-described investigation, probable cause exists to charge Corey Lewandowski.”

The Trump campaign responded in a statement asserting Lewandowski’s innocence.

“Mr. Lewandowski is absolutely innocent of this charge. He will enter a plea of not guilty and looks forward to his day in court. He is completely confident that he will be exonerated.”

Police documents say that Lewandowski was charged this morning. He was released with a notice to appear in court, police said. Jupiter Police told ABC News that Lewandowski is scheduled to appear in court on May 4.

Lewandowski’s attorney could not be immediately reached by ABC News for comment.

Florida state code categorises a first-time battery as a first-degree misdemeanor, punishable by up to one year in jail and a $1,000 fine if convicted.

Trump also tweeted, standing by his campaign manager.

Fields tweeted in response to Trump, asserting her story never changed.

Fields first spoke about the alleged incident in an op-ed published earlier this month. Fields alleges she was assaulted at Trump’s news conference on March 8, the night of the Michigan, Mississippi and Idaho Republican primaries, after posing a question to the New York real estate mogul.

“Trump acknowledged the question, but before he could answer I was jolted backwards. Someone had grabbed me tightly by the arm and yanked me down. I almost fell to the ground, but was able to maintain my balance. Nonetheless, I was shaken,” Fields wrote.

Fields shared a photo on Twitter of her bruised arm the day after the news conference.

In her op-ed, Fields went on to say The Washington Post’s Ben Terris identified the aggressor as Lewandowski.

“I watched as a man with short-cropped hair and a suit grabbed her arm and yanked her out of the way. He was Corey Lewandowski, Trump’s 41-year-old campaign manager,” Terris confirmed.

Lewandowski denied the alleged incident with Fields and called Fields “totally delusional” on Twitter.

Fields told ABC News’ Tom Llamas on March 10 there was “no excuse” for the alleged incident.

“The thing is you don’t grab a female reporter or any reporter the way that he grabbed me and you don’t do that and I just feel like there’s no excuse for it,” she said.

When Donald Trump was asked by reporters following the March 10 Republican debate in Florida about the alleged incident two days before, Trump said, “Everybody said nothing happened. Perhaps she made the story up.” (Yahoo News)

•Photo shows Lewandowski.

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