Officers scrambled to an address in Downley at 6pm yesterday after a man in his sixties was stabbed.
A policeman responding to the stabbing was shot in the leg with a crossbow.
He was taken to hospital along with the stabbing victim, and has since been discharged.
Thames Valley Police Assistant Chief Constable Tim Metcalfe said: “We are currently dealing with a serious assault and weapons incident in High Wycombe.
“A man in his sixties suffered a stab wound at an address in School Lane, Downley, at around 6pm yesterday (10/5).
“Police officers attended and one was shot in the leg with a crossbow. He was taken to hospital but has since been discharged.
“Our thoughts are with the injured officer and we are doing everything to support him and his colleagues, as well as all others affected by the incident within the force.
“The assault victim has also been taken to hospital with serious but not life-threatening injuries. Our thoughts are with him as well.
“A 54-year-old man from High Wycombe has been arrested on suspicion of attempted murder.
“He has also been taken to hospital under police supervision with potentially life-changing injuries having been shot by an armed police officer during the incident.
“We are not looking for anyone else in relation to the incident at this time.
“There is a large police presence in the area as a result but there is no ongoing threat to the wider public.
“Anyone with concerns should speak to a uniformed police officer.
“A large police cordon is in place so please avoid the area as best you can.
“I’d ask the public to avoid speculating about the incident and sharing footage on social media; instead send it to us via our website.
“We have also made a mandatory referral to the Independent Office for Police Conduct.”
More to follow.