Nighttime explorers believe they captured ghostly images of a man in a labcoat when they visited an abandoned mental health hospital in Northampton.
The group of five, who go by the name Bookeyyy Explorers, meet up weekly to venture into disused buildings across the country.
But the Peterborough-based friends believe they got more than they bargained for when they entered St Crispin's Hospital in Northampton at around 2am on Sunday morning (January 27).
Sales manager Craig Lack, 34, has described how the group made their escape from the creepy former wards shortly after his digital camera began taking photographs of its own accord.
"We went in there and started looking around the first building where the large tower is," he said.
"We couldn't get up the tower because the ladder had been cut, so we into the next building.
"We then went into one of the rooms and it was just freezing.
"We don't really do all the paranormal stuff so we thought it was just a draught.
"But the camera started going off on its own - which was strange because it would only work before when we had it pointed at the floor.
"It was only when we looked at the pictures on the camera we could make out a face and a light that we couldn't see with the naked eye.
"We went outside and the camera went off again. The picture looked like there was a doctor in a lab coat."
The two snaps taken by the Bookeyy Explorers, who say they act responsibly when they enter secured sites, are shown here.
On the top one here, a wispy white figure can be seen in the foreground, they say.
At the bottom, they say you can see what looks like the outline of a doctor in a lab coat with a stethoscope next to two shadows.
After a bit of research, Craig said other urban explorers had reported seeing a ghost here, incidentally, called Craig.
"It was very Scary," the 34-year-old added.
"Normally we don't look for this sort of thing - I'm not a non-believer, but I was in two minds."