The team behind the show are claiming to have encountered a "friendly" spirit on a number of occasions over the past year, according to the Daily Record.
A River City source told the newspaper: "Some of the sound guys have seen it, as have several of the cast. It has been known to say 'hello'. It seems to be quite a friendly spirit.
"It only appeared in the last year and it's only now that people have started talking about it. But the security guards are always talking about how there are various funny unexplained things going on around the set at night when they patrol it."
River City is filmed on a purpose-built set in Dumbarton. The site was previously the location of whisky warehouses.
The show's insider added: "Someone who worked down on the EastEnders set before coming up to River City said it was full of ghosts too. Apparently furniture has been known to move itself around there."
River City airs on Tuesdays at 8pm on BBC One Scotland.
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