David Brammer was caught on CCTV with a woman's head in his lap as he sat in the passenger seat of a car parked outside Rotherham District General Hospital in June last year.

A security guard said he became suspicious of the couple when on his rounds and later turned a security camera on them which recorded what looked like sexual activity in the car.

But Mr Brammer, who works for Yorkshire Ambulance Service NHS Trust, denied misconduct at a fitness to practise hearing at the Health Professions Council (HPC) in London yesterday.

The hearing heard from Ainsley Dale, a security officer at the hospital, who focused the security camera on the couple shortly after 11pm on June 10, making a 14-minute video.

That footage was played to the hearing behind closed doors to save Mr Brammer's "embarrassment", but afterwards Mr Dale told the panel: "In the footage, her head does go to his lap. Her head does appear to go up and down."

Under cross-examination by Lance Dodgson, representing Mr Brammer, Mr Dale said he could not tell whether the woman in the car was simply "angry and volatile" because Mr Brammer had just told her he did not want to see her any more.

Cliff Morrison, a security manager at the hospital, said the car park was brightly lit following a £0.75m lighting upgrade and the footage which he reviewed the following day was clear.

"I saw a paramedic in the vehicle," he said. "He appeared to me to be having oral sex being performed on him."

Mr Morrison denied he was "jumping to conclusions" and also revealed it was not the first time a member of staff had used the hospital car park for public sex.

"You'd be surprised, it's not the first time. It was outside in the A&E car park with a camera watching them, and members of the public have done it in our car park too.

"I'm painting a bad picture of Yorkshire people."

Sharon Witton, an investigator with the Ambulance Trust, said Mr Brammer told her he had arranged to meet the woman once and that he "had been having problems with his wife but they had decided to try again".

But she said he told her he was being pestered and stalked by the woman, who had been sending him text messages and calling him throughout his night shift, which ran from 6pm to 4am.

Yesterday, Mr Brammer, who is bald with a white beard, told the hearing: "As I've said all along, there was definitely no sexual activity in that vehicle."

He said he thought she had already realised that the pair were not "an item" and added: "I really was trying to avoid a scene. I wasn't sure if she was going to kick off."

The panel also went into closed session to discuss Mr Brammer's health and psychological issues after being told he was using the sedative temazepam at the time of his meetings with investigators.

Asked about the discrepancies in his story, he said: "I can remember nothing about this at all. I can remember virtually nothing about this."

Mr Brammer added he knew "all the places" that prostitutes used in Rotherham and said: "There were lots of places, if I were so minded, where I could have gone.

"I wouldn't wear my uniform and go under a camera in a hospital. I have never done anything like that."

During the case against him, Mr Brammer sat with his hands folded in his lap, occasionally making notes or talking to his lawyer.

Last night a spokeswoman for Yorkshire Ambulance Service NHS Trust said: "In June 2008 we conducted an investigation into claims that an employee had committed a criminal offence and breached the Trust's Code of Conduct. Appropriate disciplinary action was taken resulting in the employee being dismissed from the Trust and the case being referred to the Health Professions Council (HPC)."

The hearing was adjourned until today, when a decision is expected to be announced.