A QAnon conspiracy theorist who led a pack of Donald Trump supporters that chased a solitary police officer around the US Capitol on the day of the January 6 attack has been found guilty of several felonies.

Douglas Jensen – the bearded 43-year-old Iowa man who appeared in several media photos of the attack while wearing a black T-shirt with a large “Q” – could in theory face more than 50 years in prison after a federal jury in Washington DC convicted him on Friday, US justice department prosecutors said in a statement.

And the harshest sentence handed out so far to anyone found guilty of having a role in the deadly Capitol attack has been seven years and three months.

Jensen went around a few corners and joined a crowd that encountered a lone Capitol police officer near a stairwell, prosecutors said.

After 40 minutes, Jensen was made to exit, briefly re-entered another section of the Capitol and was forced out again, prosecutors said.