Michael Avenatti wants to fight Donald Trump Jr. in the octagon for charity

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Michael Avenatti.

• Michael Avenatti and Donald Trump Jr. have been at each other's throats on Twitter since Monday.
• At a lunch on Tuesday, Avenatti challenged Trump Jr. to a Mixed Martial Arts (MMA) charity fight, an NBC reporter tweeted.
• Avenatti confirmed it, and said he wants the money raised from the fight to go to rebuilding Puerto Rico and to a sexual assault charity.
• On Monday, Trump Jr. joked Avenatti would be running for President in 2020 with incarcerated politician Anthony Weiner - Avenatti replied Trump Jr. will be "indicted" soon and pass Weiner in jail.

US attorney and Trump administration critic Michael Avenatti challenged Donald Trump Jr. to a three-round Mixed Martial Arts (MMA) charity fight - saying "this would be for two great causes."

NBC reporter Dylan Byers was with Avenatti at the Vanity Fair Summit on Tuesday, when the lawyer and activist proposed the match-up. Byers tweeted about the proposal, and Avenatti replied, confirming it.

"This would be for two great causes. I'm in," Avenatti tweeted.

Avenatti proposed the proceeds from the fight will be "split 50% to rebuilding Puerto Rico and 50% to @RAINN," in a follow-up tweet.

RAINN are the Rape, Abuse & Incest National Network, who run a 24-hour hotline for sexual assault victims.

The tweet also said: "Just waiting on Bif [Trump Jr.] to confirm. #Basta"

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Donald Trump Jr.

Trump Jr. and Avenatti have shared barbs online this week, with Avenatti tweeting on Tuesday the president's son will "be indicted" on federal charges very soon.

The day before, Trump Jr. mocked Avenatti on Twitter, saying: "Who else is excited about Avanetti/Weiner 2020?!? It's gonna be Carlos Dangerous."

The former New York Democratic representative Anthony Weiner is serving 21 months in prison for sending obscene material to a minor at the moment, but is getting out three months early, CNN reported on Wednesday.

In response to Trump Jr's tweet, Avenatti wrote: "If I were you, the last thing I would be doing is referencing other people getting out of federal prison."

"Because after you are indicted, you will likely be passing them on your way in. BTW, they don't have silver spoons or gold toilets in the joint. Buckle up Buttercup." 

Avenatti was the attorney who submitted a lawsuit on behalf of adult-actress Stormy Daniels to repeal a 2016 non-disclosure agreement made with Donald Trump.