© ddp USA/REX/Shutterstock Violent protests in DC streets after Donald Trump inauguration on Friday. Four more journalists have been charged with felonies after being arrested while covering the unrest around Donald Trump’s inauguration, meaning that at least six media workers are facing up to 10 years in prison and a $25,000 fine if convicted.

A documentary producer, a photojournalist, a live-streamer and a freelance reporter were each charged with the most serious level of offense under Washington DC’s law against rioting, after being caught up in the police action against demonstrators.

The Guardian learned of their arrests after reporting on Monday that the journalists Evan Engel of Vocativ and Alex Rubinstein of RT America had also been taken into custody by police and charged with felonies while covering the same unrest on Friday morning.

Jack Keller, a producer for the web documentary series Story of America, said that he was detained for about 36 hours after being kettled by police at 12th and L streets on Friday morning and then arrested despite telling officers that he was covering the demonstrations as a journalist.

“The way we were treated was an absolute travesty,” said Keller, whose cellphone has been kept by the authorities. Keller’s editor, Annabel Park, said: “It is a maddening and frustrating situation. These are people who were there observing and documenting.”

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Matt Hopard, an independent journalist who was live-streaming the Friday protests, was arrested at the same site as Keller, Engel and Rubinstein, according to metropolitan police records. He said in a message that he denied the charge against him.

Also arrested while covering the demonstrations at 12th and L streets were Shay Horse, an independent photojournalist and activist, and Aaron Cantú, a freelance journalist and activist, who has written for outlets including the Baffler, the Washington Spectator and the New Inquiry. Both deny wrongdoing.