Natasha Wright was with her 11-month-old son, Nathan, and her partner when she was walking through an alleyway in Lincoln on Friday at 3pm.
The 19-year-old said she was “shocked” after she saw him “wiping himself with his boxers and chucked them in the bush”.
She said: “We were coming back through the bridge when we saw him completely naked.
“It seemed like he was touching himself. After touching himself he’s then wiped himself with his boxers and chucked them in the bush”
”He was facing the other direction, we could see his bum.
“It seemed like he was touching himself. After touching himself he’s then wiped himself with his boxers and chucked them in the bush.”
Natasha said she was left speechless at the site.
She added: “He finished and just walked past us. He went ‘there’s no need to stand there and look’ and walked past us laughing.”
She said it is a horrible things to do as there were children using the path at the same time.
Natasha said: “Kids use the bridge to get to and from the park.
”There were two kids on bikes who were about 12-years-old who looked like they didn’t know what to do.
“Our garden backs on to that alleyway and I use it quite regularly. It’s disgusting.
“If you do really need to go there’s plenty of bushes nearby, use one of those, but it didn’t look like he was that desperate.”