'Coronation Street' actor Jack P. Shepherd pretended to urinate on the 'Emmerdale' sign.
The 27-year-old actor - who plays David Platt on the Manchester-based soap - posted a picture on Twitter of him apparently relieving himself on the sign while at a party on the set of the rival ITV soap.
A source said: "Jack had a few drinks like the rest of the 'Corrie' cast, but as the night went on he got a bit boisterous."
However, Jack - who was reprimanded for posting insensitive comments on his Twitter account last year - quickly bottled it and took down the snap for fear of upsetting his bosses once again.
The insider told The Sun newspaper: "He thought it would be funny to pose for this snap and posted it online, but took it down within seconds.
"Jack knew this could get him in trouble. There's a big rivalry between the soaps but the ITV bosses don't want any headaches over rows.
"Jack's been in trouble before as well and they've all been warned about how they use social media."
Meanwhile, Lucy Fallon - who plays Jack's on-screen niece Bethany - also posted pictures on Twitter, posing outside Emmerdale's Woolpack pub with Paula Lane and Tina O'Brien - who play Jack's on-screen wife Kylie and sister Sarah-Louise.
The 19-year-old actress shared: "Had a bit too much fun last night at the summer party."
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