Robbers armed with a one foot long machete have terrorised bus passengers on a rampage in Harold Hill.

Their first victim was a 16-year-old boy. He was ambushed on Tuesday last week while he was sitting alone on the top deck of a 174 bus travelling along Straight Road, at 8.40pm.

One of the robbers asked to see the teenager's £200 gold chunky bracelet. When the youngster asked for it back he was threatened with the deadly 12in blade. The pair then jumped off the bus leaving their victim shaking.

The pair then moved on to carry out a second raid nearby on the top deck of a 374 bus, in Faringdon Avenue, at about 9pm.

Again they targeted a lone 16-year-old teenager. The victim told police they threatened to kill him unless he handed over his mobile telephone, which they grabbed before jumping off the bus.

The attackers were described as black men aged between 18 and 20. One man was 5ft 7in tall and wore a baseball cap, faded red jeans and a dark jumper.

His accomplice was 6ft 2 to 4in tall with short black hair with a razor line. He was scarred on both cheeks. Both men spoke in a foreign language to each other.

Sgt Mick Adamson from Harold Hill Police said: "These are very serious and worrying attacks. We will be in liaison with the bus companies to see if there is any CCTV footage from the hidden cameras.

"Thankfully, no-one was physically hurt - but the attacks are very much a cause for concern. I would advise people to sit downstairs on buses, especially late at night and not to approach these men."

There was a another attack on a 374 bus the same day at 3.45pm in Straight Road. A black boy aged about 15 and 5ft 5in tall wearing a blue Adidas jumper, dark jeans and black Reebok trainers punched a 12-year-old boy in the face, leaving him with a black eye.

Sgt Adamson appealed for witnesses to the attacks to contact police on 01708 779241 or Crimestoppers on 0800 555111

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