A man "aggressively" begged a teenager for money so much she was forced to knock on a stranger's door for safety.

Police say they are aware of social media reports of an incident in Watford Road, Croxley Green, at around 8pm yesterday - but they are not linking it to an ongoing investigation of schoolchildren being approached.

Police have confirmed a 16-year-old girl was walking near Croxley station when she was approached by a man who asked her for money.

The girl became so frightened she hurriedly walked away but realising the man was following her, she knocked on the door of a nearby house for help.

Officers were called to the scene and spoke to the girl and her mother but the beggar had already left the area.

Police were told the man was Asian and aged in his 20s - but after studying CCTV, they have identified the suspect as white.

Sergeant Neil Canning, from the Rickmansworth and Croxley Green safer neighbourhood team, said: "This was an understandably unsettling incident for the young girl and officers attended to speak to her and her mother.

"We know the public will have at the forefront of their minds the previous incidents in Three Rivers last week where a man reportedly approached schoolchildren.

"However we received another call earlier yesterday evening from a male member of the public who told us he was approached by a man matching the same description.

"The man had told the caller he was homeless and began aggressively begging for money so we believe this to be the same man who approached the girl.

"Following CCTV enquiries, we have identified the suspect as a white male. Therefore we are satisfied this is an isolated incident, so we are not linking it to our investigations into the other reports."

Police say they will be keeping an eye out for the beggar.

Investigations remain ongoing into reports of schoolchildren being approached across Three Rivers and Watford.

Police have told us of at least four reports of children as young as 10 and 11 being approached in Rickmansworth, Chorleywood, and Watford since the beginning of last week.

The most recent incident we are aware of was yesterday morning when an Asian man asked an 11-year-old boy if he wanted a lift in his van in Sheepcot Lane.

Read more: Driver asks Watford schoolboy to get in his van

However, police say an incident involving a 16-year-old boy in Oakfield, Mill End, on Friday, was a case of mistaken identity.

After reviewing CCTV and carrying out door-to-door enquiries, police say the Asian man in a black vehicle who asked a boy into his car, was a taxi driver and he thought the 16-year-old was his customer.

Sergeant Canning: “We are satisfied that this incident is not suspicious and therefore not linked to previous reports in Three Rivers. We have made contact with the boy, his family and his school to inform them of the outcome.

“We are progressing with our enquiries into the other incidents reportedly involving an Asian male approaching children. We continue to encourage young people to be vigilant and report any suspicious activity to us. If you feel in danger, please do not hesitate to call 999.”