The director of a clearance firm says staff have been left "pretty shaken up" after lumps of frozen mud were thrown from a bridge, smashing their van's windscreen.

Workers from family-run Whitstable business ClearaGem were driving home along the London-bound A299 Thanet Way when the solid mounds were launched from the Crab and Winkle footpath bridge, hitting several vehicles.

Manager Steve Ramsey was dropping the company van off after work when the sudden impact almost caused him to crash at about 6.30pm on Tuesday.

The van's windscreen was smashed and wing mirror damaged, while another vehicle's sunroof was shattered, and a further car's bonnet was dented.

Police have condemned the "extremely dangerous" attack, adding it was "sheer luck" no one was seriously hurt.

Clearagem company director Gemma Phillips heard about the incident after her manager pulled into her driveway in the damaged Luton van shortly after it happened.

“It could have caused a massive accident," she said.

"They handled it really, really well and managed to get the van home safely but they were pretty shaken up.

“It all happened so quickly. At first they thought something had come off a lorry and hit the van but there were just two cars ahead so it must have come from a bridge.”

Mrs Phillips continued: “It was definitely intentional, I don’t think it could have been anything other than either a kid or someone who has clearly lost the plot.”

As soon as they were sure nobody had been injured they reported the incident to the police, wary this could happen to another driver with more dire consequences.

The ClearaGem boss said: “We rang Kent police and they gave us reference number and said that was pretty much all they could do.

“But there’s no cameras along there or anywhere to pull any evidence to find out who did this. Someone has got away with this.

"We’re just lucky and grateful that nothing worse came of it because it could have been a lot worse.”

While Mrs Phillips is grateful her staff managed to escape unscathed, she now has to deal with the impact this will have on her business.

The repairs to the windscreen and the damaged wing mirror will amount to at least £300, and the two days of work lost while the van is out of action will add to the costs.

Mrs Phillips had hoped to hire a van to avoid disappointing customers, but was unable to find any appropriate vehicles at such short notice.

“I don’t think people will realise that not only could it have been life-threatening, it will also really cost us as a business," she said.

“It is a serious matter and it has affected the business as it has added stress and pressure at a time when that really isn’t needed.

“But everyone has been very supportive and very caring. We are a fairly well-known business in Whitstable because we support the Pilgrim’s Hospice."

Police confirmed the incident had been reported and "officers are assessing the information provided".

The force has since issued an appeal for anyone with information or dashcam footage to come forward.

Investigating officer Sergeant Stephen Wells said: "Throwing items from heights towards oncoming vehicles is extremely dangerous and it is only sheer luck that nobody was seriously hurt.

"We have been making enquiries in the area to identify suspects and I am appealing for anyone with information or dashcam footage that may assist the investigation, to contact us."

Witnesses are urged to call police on 01843 222289, quoting the crime reference number 13-1124, or Crimestoppers, anonymously, on 0800 555111.