Four teenagers have been arrested after a 20-year-old cyclist was attacked and had his bike taken in a violent ambush in broad daylight in a park just north of Birmingham earlier this week.

The cyclist was left with broken fingers and a swollen face – after being struck by a metal bar – following the terrifying bikejacking, which took place on Thursday afternoon at around 3pm near Blackroot Pool in Sutton Park, a large nature reserve six miles outside Birmingham.

Posting a photo of the stolen Vitus mountain bike – which had been bought by the 20-year-old just days before the attack – on Facebook, the cyclist’s mum said that her son had been ambushed by “six to eight young men in balaclavas [and] on motorbikes and electric scooters”.

The rider was struck by a metal bar across the face and body during the violent robbery, while his fingers were also broken as the thieves attempted to force him to release his bike. The cyclist then attempted to run and throw the bike in a nearby lake, but the attackers caught up with him, hitting him with the bar and threatening to stab him before taking his bike.

Police were called to Sutton Park and took the cyclist to hospital, where he was treated for two broken fingers and a “very swollen” face.

> “It’s just not safe”: Cyclist raises alarm after another violent bikejacking on popular route

Speaking to the Birmingham Mail, the cyclist’s mum said: “My son is 20-years-old and had only had the bike for two days. He saw the group and they grabbed hold of him as he went to go by. He tried to get away and he said he wouldn’t give his bike up. They threatened to stab him. And he said, ‘you’re going to stab me over a bike?’.

“He then pushed them off and they were wrestling with him. He managed to pick up his bike and was going to throw it in the pool as he thought they wouldn’t get it from there. He’d bought it for nearly two grand from his grant money. But he didn’t get anywhere near the lake.”

She continued: “His face was a mess, his nose was bleeding, and his fingers were broken. They also asked for his phone and he told them to f*** off. He was angry and they left him. He called the police who sent police cars after them and caught four of them.”

> Cyclist warns of yet another terrifying knifepoint bikejacking

West Midlands Police later confirmed that four teenagers, aged between 13 and 19, were arrested in connection with the incident.

“We’ve arrested four people after a man was assaulted and robbed of his bike in Sutton Park on Thursday (April 13) afternoon,” a police spokesperson said.

“A 20-year-old man reported being struck by a metal bar. Following quick-time enquiries we arrested three boys – a 13-year-old, two aged 17, and a 19-year-old man – on suspicion of robbery. They have been bailed with conditions while enquiries continue.”

> What can be done about the latest spate of bikejackings?

The shocking incident in Birmingham is the latest in an increasingly long line of violent bikejackings to have plagued the UK in recent months.

Last month, a London cyclist was attacked and had his bike stolen by two masked men during an ambush on a popular cycle route, not far from the scene of previous similar bikejackings.

road.cc reader Ben was left bleeding “fairly profusely” after being struck in the nose during the attack, just months after another cyclist was threatened with a “foot-long knife” on the same South Bermondsey stretch of Cycleway 10, where graffiti warning cyclists of attacks had been previously daubed.

In February, a cyclist was knocked from his bicycle by masked men and threatened with a knife during an attack on his ride home from work through an East London park, while just before Christmas three masked men armed with machetes attacked a cyclist, stealing his bike and phone, and threatened a passer-by earlier on a busy riverside path in Bristol.

That attack came less than a month after a group of youths, believed to be aged between 12 and 16, attempted to rob a woman of her bike and handbag on a cycle path close to Filton Abbey Wood railway station, to the north of Bristol.