A 13-year-old boy jumped into action after seeing what he believes was a man exposing his genitals to women and children in a McDonald's restaurant.

Frankie Mason, from Bexleyheath, had just gone to get a double quarter pounder, chips and Coke with his friend when he noticed the man.

The incident took place in the Bexleyheath branch of McDonald's, on the Broadway, between 7-8pm on Tuesday.

The 13-year-old went to help after he heard a woman screaming in the restaurant. He saw a man standing in front of two women and four boys, and says the man had his penis out.

He said: "Security were just talking to him."

Frankie tapped the man on his shoulder, which made him re-cover himself.

The man then started to act aggressively towards Frankie who then walked him outside and told him to "jog on."

"There was another woman shouting at him to put it away as well," he said.

Once escorted out, Frankie said the man hung around outside for a bit, before moving on to a bus stop.

Frankie's mum, Jackie, reported the incident to police, although they have been unable to confirm they have received the report.

She said that on the evening of September 29, she received a call from the McDonald's branch, who said they had looked at the CCTV.

"They said that there's nothing to show that he had his bits out – they described the situation as teenagers goading a little old man," she said.

She is unhappy with the fast-food chain's response.

She added: "I’m very proud of my son for helping the ladies but part of me wished he hadn't confronted the guy, for reasons of the retaliation now is frightening."

McDonald's has been approached for comment.