Drivers who resent cyclists' ability to dodge traffic could be behind a series of attacks on riders in and around a city, a cycling group has said.
Thames Valley Police say three attacks on cyclists may be linked
In the latest incident, on Monday, a 26-year-old man was shoved from his bike in Abingdon, south of Oxford.
He sustained bruising and cuts to his knees, elbows and hips.
Oxford-based pressure group Cyclox believes angry drivers are targeting cyclists. Police are investigating links between the attacks.
Cyclox spokesman James Styring said: "There are more people taking to their bikes because of summer and maybe motorists get annoyed with their ability to skip traffic queues.
"Although it may seem like an amusing summer activity driving along and pushing people off their bikes, if someone breaks their neck you could be facing a murder charge."
Thames Valley Police believe the latest attack near the Ox public house on the A4183 on Monday could be linked to two others in south Oxfordshire.
The first known attack was on a 32-year-old woman, who had abuse hurled at her and was punched by two men travelling in passing cars as she cycled along the Banbury Road in Summertown, north Oxford, on the morning of 12 June.
In mid-June, a 68-year-old man was pushed off his bike by someone in a small white van on the B4009 just outside Princes Risborough.
The victim of Monday's attack told police he remembered hearing a diesel engine and glimpsing a white vehicle, possibly a van, passing him.
Pc Lewis Boyce, investigating the Abingdon incident, said: "I am aware that there have been a number of similar incidents involving cyclists being pushed from their bikes and I will be looking into these to see if there are any clear links.
"This is no prank. Falling from a cycle could easily cause a serious injury and could even prove fatal, particularly if the cyclist were to fall into the path of an oncoming vehicle."