Tree felling in Sheffield has been halted after a clash between tree protesters and security staff on a city street.
Sheffield Council is to review the processes in place when arborists are felling trees after a series of incidents where safety cordons were breached by protesters in a bid to stop the work.
There was a disturbance in Meersbrook Park Road, Meersbrook, on Monday, when a campaigner fighting to save the trees clashed with security staff, who have been given permission to physically remove trespassers from safety zones.
Council contractor Amey is felling trees across the city as part of a £2 billion road improvement programme.
Arborists are felling trees deemed dangerous, dead, diseased, dying or which are said to be damaging streets and pavements.
Objectors to the scheme have staged a number of protests across the city, with demonstrations now held on a daily basis.
Trees earmarked for felling are fenced or cordoned off and a court injunction is in place making it illegal for protesters to enter the safety zones.
But a number of cordons have been breached, leading to a number of stand-offs.
An Amey spokeswoman said: "We welcome safe and peaceful protest but unfortunately this is not what we experienced in Meersbrook Park Road on Monday.
"In the interests of everyone’s safety we withdrew from site, and we will resume as soon as we can ensure the safety of our staff, local people and the protesters themselves.
"Re-planting certain street trees which are ailing or damaging is one of the ways we deliver the council’s legal duty to maintain the city’s highways, which is why a High Court injunction is in place to keep our working areas safe.
"We urge people to respect peaceful communities and not to wilfully obstruct our works on the highway by staying outside the safety zones, so we can complete this programme for the benefit of everyone in Sheffield."
A South Yorkshire Police spokesman said an investigation into the Meersbrook Park Road incident is underway.
"We have received a number of allegations of assault in relation to this matter.
"Police are now reviewing these reports. Enquiries are ongoing and anyone with information is asked to contact 101."