A 31-year-old man accused of stabbing a fellow competitor at a convention for fans of the Channel 4 quiz show Countdown has been ruled unfit to stand trial, and a finding of fact hearing opened at Preston Crown Court on Wednesday.

John Cowen is alleged to have run toward fellow club member Thomas Carey at a gathering at the Wainwright Club in Blackpool on September 14 last year, lunged at him with a kitchen knife and stabbed him in the upper arm, jurors were told. CCTV footage shown in court was described by the prosecution as showing Cowen striking Mr Carey before other attendees overpowered him.

Prosecutor Rosalind Scott Bell told the court that members of a social club called the Focal Countdown group meet regularly to play and socialise. At about 11:30 a.m. on the day of the incident, Mr Carey was speaking with two people in a function room when Cowen entered holding a knife in his left hand, the court heard.

"Mr Carey recalled hearing Cowen 'growling' before he appeared to 'clock' him and ran towards him," the prosecutor told jurors. She said the defendant lunged across a table toward Mr Carey's upper torso, forcing him backward onto a seat. Mr Carey sustained a wound to his bicep, kicked out at Cowen and grabbed his wrist in an effort to stop the assault, the prosecution said.

Other club members are said to have pulled Cowen away, disarmed him and restrained him on the floor while police were contacted. Officers who arrived at the scene allegedly found a second, identical kitchen knife in Cowen's pocket. Mr Carey was taken to hospital and treated with steri-strips for the wound.

Cowen faces a charge of wounding with intent contrary to section 18 of the Offences Against the Person Act and two counts of possession of a bladed article, jurors were told. At the start of proceedings potential jurors were asked whether they had been contestants on Countdown, members of its fan club or avid viewers; all indicated they were not.

Judge Guy Mathieson told the court that Cowen has been assessed as "seriously mentally unwell" and is currently detained in hospital, making him unable to participate in or attend trial. Because of that medical finding, the court is conducting a fact-finding hearing in lieu of a full trial. Jurors at the hearing will be asked to determine whether Cowen carried out the stabbing but not to assess his intention at the time of the incident.

Jurors were also told that Mr Carey had been a member of the Focal Countdown group since about 2011, while Cowen was not a regular attendee of the club. The hearing continues and the court has yet to rule on the outcome of the fact-finding proceedings.

The proceedings at Preston Crown Court clarified legal steps taken when a defendant is found unfit to stand trial because of mental disorder. In such cases, a finding of fact hearing establishes what acts occurred; any consideration of criminal responsibility or later measures is dealt with separately under statute and sentencing and disposal rules that apply to defendants detained for treatment.

No further comment was provided in court during the hearing, and police and court officials did not immediately release additional details about medical assessments or the defendant's current treatment. The case remains listed for continued hearings to hear evidence relevant to the alleged stabbing.