A bitter break up between a millionaire businessman and his fiancée has ended in court following an ugly row involving £5,000 criminal damage to a Mercedes car.

Max Walker claimed he was threatened by his ex's brother, Matthew Vowles, who then allegedly took a hammer to his luxury car when he went to their former family home in Poole to track down some missing yacht sails.

Mr Walker had parked in front of the £2million house and was waiting for the police to meet him there when Mr Vowles came out of the property shouting and being aggressive.

He said he felt intimidated and dialled 999 but alleged Mr Vowles then went back to his van and returned with a hammer which he used to try to smash the passenger window and then scratched the paintwork of his Mercedes S500.

Mr Vowles was charged with criminal damage and using threatening words or behaviour to cause harassment, alarm or distress for the incident on August 6 last year.

He pleaded not guilty and was acquitted at Bournemouth Magistrates' Court on Wednesday.

Mr Vowles told the court he was trying to leave the house to go to a boat party when he found Mr Walker blocking the driveway and got frustrated.

He admitted shouting but said he never made any threats and never damaged the car, only asked him repeatedly to move his car.

Mr Vowles, who is a builder, said he had a hammer on his toolbelt, which he was still wearing, but never used it.

The court also heard from eyewitness Simon Morse, who lived across the road and was in his bedroom at the time of the incident.

He told the court: "I noticed a black Mercedes because it was the only car in the road but despite that it had parked in front of the gates.

"A driver got out of a truck and walked towards the Mercedes shouting for the car to move. He seemed cross and frustrated.

"There was a conversation between the two drivers I couldn't hear then the truck driver went back to the truck and reappeared moments later carrying a lump hammer so I called the police.

"He continued to ask the Mercedes driver to move then struck the passenger side very forcefully with the hammer several times.

"It looked to me he was hitting it as hard as he possibly could. It was all aimed at the window but despite the force the window didn't shatter."

But Mr Morse said although his view was partially obscured by the car he didn't see any actions to show any damage being done to the bodywork.

Defending Mr Vowles Kate Fenwick told the court the Crown had not proven their case beyond reasonable doubt and there was no evidence that showed Mr Vowles had caused the damage.

She said the recordings made by Mr Walker do not show a hammer and it was not plausible that a car window hit with a hammer repeatedly would not smash.

Miss Fenwick said: "It's very clear that there is quite a lot of bad blood between the complainant and Mr Vowles. Both parties allude to a long and unpleasant history.

"Mr Walker says he attended in a peaceful manner but there is no evidence of that. The entire road was clear of traffic, he could have parked anywhere but parked directly outside the gates.

"He was clearly expecting a scene on his arrival, he chose to position himself in a way that would inflame an already fragile situation.

"It would annoy even the calmest person and he had an entirely reasonable reaction.

"If he was so worried he could have moved off safe in the knowledge the police were already attending on another matter.

"The damage to the vehicle is completely inconsistent with a vehicle that has been attacked with a hammer and the recordings don't show my client damaging the car."

Mr Walker said he didn't drive off as he had his phone in one hand dialling 999 and an iPod in his other trying to record what was happening and he was in shock at the aggression and violence.

He said he hadn't been able to get the iPod recording quickly enough to capture the hammer attack and didn't know why the glass did not smash.

He also told the court he heard "grinding noises" as Mr Vowles scraped the bodywork.

The magistrates said Mr Walker did not sound in fear and had ample opportunity to remove himself, but his demeanour appeared provocative, while Mr Vowles had repeatedly requested that he move.

Speaking after the case Mr Walker, 52, said: "I think it's an absolute travesty. Because I didn't manage to video the first half it's as if it didn't happen and I'm left with £5,000 worth of damage. It's just shocking."

Mr Vowles said he was relieved the case was over and claimed Mr Walker had put his family "through 12 years of hell".

Mr Walker was in a relationship with Rebecca Vowles for 12 years and proposed to her in 2009 by stitching "Will you marry me?" onto the sails of his 38ft yacht.

But the relationship hit the rocks in 2012 and the break-up kick-started a string of civil court cases.