An Obama appointee in the Department of Education allegedly insulted, spat on and savagely beat an autistic Native American man for wearing a Redskins sweater.

Barrett Dahl, 28, says he was at a Native American gathering in Washington, DC in October 2015 when appointee William Mendoza spotted him wearing the sweater.

'He comes to me and says you're a "weetard" for wearing a Redskins shirt,' Dahl told KFOR. 'He says where are you from that you're such a "weetard," you don't understand that you're offending me?'

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Autistic: Barrett Dahl (pictured) says he was assaulted by a White House appointee in October after the man saw him wearing a Redskins sweater. Dahl is autistic

Fight: William Mendoza allegedly insulted, spat on and assaulted Dahl. Mendoza is a Native Affairs expert in the Department of Education; both he and Dahl are Native American

Hospitalized: Dahl said he had to have three operations after the fight that have cost him $40,000 - and left his parents at risk of foreclosure. Mendoza says Dahl started the scuffle

Mendoza is of the Oglala-Sicangu Lakota people, and an appointee dealing with Native American affairs in the Department of Education.

He is an opponent of organizations like the Redskins using Native American people as mascots.

Dahl, from Oregon, is part of the Sac and Fox Nation. He said he wore a sweater with the team's controversial logo because he felt 'cultural pride' while at the Pow Wow on October 30 last year.

But for Mendoza, Dahl claims, it was a step too far. 'He spits right in my face,' Dahl said.

'The boy sitting next to me sees it. He doesn't say anything. So, I get up and leave the ballroom to get the police.'

Dahl says that's when Mendoza approached him on an escalator and beat him so savagely he wound up with a fractured arm, broken teeth and a black eye.

Medical bills - including three surgeries - came to $40,000, he said, and now his parents are facing foreclosure.

Fracture: Dahl was left with a fractured arm, broken teeth and a black eye. Mendoza says he verbally confronted Dahl about the sweater but later apologized - then Dahl attacked him

Bruise: Dahl says he was left with this bruise on his chest after the fight. Dahl says he feels 'cultural pride' about the controversial Redskins logo, which Mendoza opposes

'What bothers me the most about this, first off, we've lost everything we have and he's lost nothing,' he said. 'He's kept his job, his home, his family.

'And, second off, there's not a doubt in my mind that this person would do the same thing to a young child who was wearing a Redskins shirt.'

But Mendoza told News9 that he politely asked about the words 'INJUN PIMP' on the back of Dahl's shirt, and that Dahl responded violently.

According to the appointee, Dahl said: 'I don't have to (expletive) explain (expletive) to you. If you want to step outside and take this outside, I'd be happy to explain it to you.'

Dahl says his shirt said 'INJUN PLAYER.'

Mendoza says he offered Dahl his hand after seeing him on the escalator and apologized for upsetting him, but Dahl then attacked.

Punch-up: Mendoza (pictured after their scuffle) says that Dahl threw coffee in his face before attacking him, and that Dahl received his injuries after they fell over together

Black eye: Dahl had a black eye after the fight. He is planning to sue Mendoza

'He was holding a cup in his hand,' Mendoza wrote, 'at which point, he threw its contents that was the smell of coffee and was hot, but not scalding.

'He then punched me in the face (right cheek). I tried to grab him but we both fell.'

Dahl says he plans to sue Mendoza for medical expenses. Mendoza's lawyer says his client will sue Dahl if he 'continue(s) to malign' him.

Mendoza became the executive director of the White House Initiative on American Indian and Alaska Native Education in December 2011, when it was created by executive order by President Barack Obama.