A man has been left gobsmacked after discovering a secret room in his grandad's house - and now he doesn't know whether he should contact the police.

He explained how his grandad moved into a new house "in the country" and when visiting him one day, he accidentally damaged a wall in the property.

After taking a closer look at the damage, he noticed something unusual and called his grandad in to have a further look. On Reddit, he said: "I went to visit my grandparents a few months after they had moved into a new house out in the country. I got into a bit of horseplay with a cousin and got shoved into a wall. It broke a big hole and we realised there was a large empty space back there."

With his grandad's help, the trio tore down the wall - but they weren't at all prepared for what they saw on the other side. He added: "We found a little room full of planting trays and grow lamps. There were a number of books about horticulture and one specifically about growing marijuana.

"There was no secret way in as far as we could tell. Someone had just walled the entire room off for some reason." Commenting on his post, one user said: "Your poor grandpa having to pretend to be seeing his own grow-op for the first time while showing it to his grandkids."

Another user added: " I'm guessing they walled it off so they could sell the house/not have evidence lying around of their marijuana growing." A third user said: "Nice try grandpa."

But it turns out he isn't the only one to have uncovered a grow room in their house as another user added: "In a house, a friend was renting. I realised that there was a missing 5 feet between the back wall of the master bedroom and the back wall of the garage.

"Poking around the garage I found a piece of plywood with concealed hinges, held shut with two nails. Opened it and found a 12 by 5 room with walls covered with foil and a couple of outlets for lamps on the ceiling. My friend converted it into a walk-in closet."