Hammer-wielding robbers prowling the streets on high-speed mopeds are growing more “cocky” according to a stockbroker mugged in front of his children this week.

Ham & High: Alexander Merkel, Watford.Alexander Merkel, Watford. (Image: EMPICS Sport)

A boy of four and his seven-year-old sister watched in horror as their parents were threatened with a hammer as one of the most brazen and terrifying raids yet took place in broad daylight on Saturday afternoon.

Three thugs on two scooters surrounded the family in Winnington Road, Hampstead Garden Suburb, as they climbed into their 4x4 after a day out at Kenwood.

Menacingly clad in dark boiler suits and crash helmets, they swung the hammer into the car before demanding the couple’s luxury watches – a Rolex and Hublot worth £10,000 each.

The father, 35, a stockbroker who lives in the Suburb, said: “I was helping the kids into the car when all of a sudden a hammer goes bang onto the side of the car – an inch from my head.

“I turned round and saw the guy with hammer, he asked for our watches, we gave them up and then they drove off.

“It was like something out of a film. I couldn’t believe what was happening to me.

“They surrounded the car and were revving the engines – you could hardly hear or see anything because of the smoke and noise.”

Officers are now linking at least six moped robberies carried out in Hampstead Garden Suburb, Hampstead and surrounding areas in recent weeks.

The robbers are believed to target people with expensive cars, sometimes ramming their bikes into houses with luxury vehicles parked outside.

The stockbroker fears those responsible for the crime spree are “getting more cocky”.

“There were a lot of people in the street,” he said.

“No-one called the police – everyone was too scared. It’s quite intimidating.”

An almost identical mugging took place in another Suburb street on Wednesday last week.

Meanwhile, police this week issued CCTV images from yet another moped robbery involving a hammer on Friday, April 11.

This time, four men reportedly stole a £60,000 watch after attacking a 57-year-old while he was sweeping his driveway in Platts Lane, Hampstead.

Cllr Danny Seal, Barnet Council member for Garden Suburb ward, said: “I know police are increasing patrols in the area.

“Unfortunately, we are dealing with very nasty people. This is a very organised and determined gang who have been planning this.

“It’s very scary, but then we also have to live our lives. We can’t let the criminals win – but we have to be vigilant.”

German footballer Alexander Merkel, who plays for Watford, was targeted at his Hampstead home on Friday, May 2.

On that occasion, the culprits attempted to batter down his front door by ramming it with their scooters.

The Ham&High reported in February that Suburb residents were fitting bars and reinforced doors to protect their homes after a similar spate of robberies.

Detectives from Barnet and Camden police declined repeated requests to speak to the Ham&High this week.

n Anyone with information on the incidents can call police on 101 or Crimestoppers anonymously on 0800 555 111.