Grass cutters in Bradford will be given guards after being forced to flee stone-throwing yobs, who sprayed one worker in the face with weedkiller and threatened another with a knife.

The council workers have been subject to a string of vicious assaults as they tried to mow grass in Undercliffe - and had to retreat for fear of serious injury.

They even tried sneaking back early in the morning to finish cutting the grass in a bid to avoid being attacked.

But now park rangers will stand guard over them when they return to the Greenway public footpath off Otley Road.

Council bosses are relieved none of the staff have been seriously injured - despite one worker being sprayed with weedkiller.

Today Councillor Anne Hawkesworth, Executive Committee member for environment, described the incidents as 'shameful'.

She said: "It is absolutely disgraceful that people should need protection when they are working for the good of the community.

"It is totally wrong that there should be 'no go' areas in this district."

She said the Council would consider using its new anti-social behaviour orders against the teenagers, who could be ordered by courts to behave or go to prison.

A council spokesman said: "Sadly, we have not been able to cut the grass in parts of Underlcliffe for four weeks because council workers have been repeatedly stoned by youths and threatened with a knife on one occasion"

She said council workers usually went out in groups of two or three, using small machines.

"There have been eight incidents of stoning, usually involving half a dozen teenagers and on one occasion a worker was sprayed in the face with the chemical lance he was using. We had to pull out because it was not safe for the workers to continue."

She said the police had been told and the council's community safety officer, Sharmilla Ghandi, and Bradford North Area Panel co-ordinator Bullah Singh were working with staff.

"We have managed to cut some of the grass early one morning and are going to use the mobile park rangers to act as escorts next time," a council spokesman said.

Today a resident said stones were also being thrown at windows in the area and other people had been attacked.

Kathleen Brooke, 60, said: "I think it is very sad if workers who are doing things for us have to be protected. There are a lot of very frail people in their 80s and 90s who are worried.

Coun Hawkesworth appealed for anyone who knew the culprits to call the police or the council.

A West Yorkshire Police spokesman said officers were aware of the problem and were working with the council to seek a resolution.

The attackers were also slammed by Tory ward councillor Alam Intkhab as disgraceful.

He said: "People in this ward ask for improvements in the environment like grass cutting. We do our best but workers should not be in danger."