The 35-year-old was found with a note in his pocket setting out his plan of attack.

Midweek Herald: Steven McMahon had only been free for a few weeks when he lay in wait for victim Benjamin Watkins. Picture: D&C Police.Steven McMahon had only been free for a few weeks when he lay in wait for victim Benjamin Watkins. Picture: D&C Police. (Image: Archant)

A violent ex prisoner has been found guilty of carrying out a hammer attack on his girlfriend’s former partner.

Steven McMahon had only been free for a few weeks when he lay in wait for victim Benjamin Watkins and hit him repeatedly around the head with a hammer.

After his arrest, police found a note in his pocket in which he planned the attack and an eye witness saw him hanging around Axminster waiting for Mr Watkins.

He was angry because Mr Watkins had found out about his relationship with his ex partner Kelly Westlake and had alerted police about McMahon staying at her home, where there were two young children living.

Mr Watkins had been to the house in Foxhill, Axminster, earlier on the day of the attack to raise his concerns and was attacked after returning later the same day.

He arrived at the house to find the windows blacked out with bin bags and tape and there was a gap before Miss Westlake opened the door.

McMahon had slipped out the back door, crossed the street and was hiding behind a van opposite, lying in wait. The plan was set out on the note found in his pocket which read: ‘go out bk door, wait for him there, do whatever’.

He caught up with Mr Watkins in Lyme Close and he was left covered in blood after being hit four times on the head.

McMahon returned to Foxhill, collected his moped, and fled before police arrived. He was arrested the next day when he went to a doctor’s surgery in Chard with a head injury, apparently suffered during the struggle.

He has four previous convictions for violence and was on prison licence after being released half was through an eight year, ten month sentence imposed in June 2014 for a robbery in which he stabbed a pizza delivery man in Seaton.

McMahon, aged 35, of Clinton Rise, Beer, denies wounding with intent to cause grievous bodily harm, wounding, and possession of a hammer and knife in a public place.

He was cleared of wounding with intent and having a knife but found guilty of wounding and possessing the hammer as an offensive weapon.

Judge David Evans adjourned his case at Exeter Crown Court and ordered the probation service to carry out an assessment on whether he is a dangerous offender.

He said: “I need to consider dangerousness. It might be that it is quite clear you are dangerous but I will need a report nonetheless.”

During the trial the jury heard how Mr Watkins had been in a relationship with Miss Westlake but they had broken up and she was with McMahon at the time of the attack in July.

Mr Watkins had been to see her at her home in Foxhill, Axminster in the morning of the 29th and they had argued. He went back at around 9.30 pm and found the windows and letter box blacked out with tape or black plastic.

Miss Westlake let him in but he noticed a motorcycle helmet in the house and felt there was an uncomfortable atmosphere when he asked her about it.

He left on foot but when he reached Lyme Close, he realised McMahon was following him and turned back to talk to him.

He saw McMahon with both arms outstretched with a claw hammer in one hand and what he thought was a hunting knife in the other, saying ‘do you want some?’.

There was a fight in which Mr Watkins suffered hammer shaped wounds to his forehead and nose.

McMahon told the jury he was acting in self defence after Mr Watkins rushed at him and rugby tackled him.

He said he had the hammer with him because he had been working on his bike and was holding it as he tried to fend off the other man. He said he had no intention of injuring him.