A group of school students were threatened at knifepoint in Admirals Park, Chelmsford, it has been reported. 

Hylands School has sent an email to parents today, following the incident which is believed to have taken place this morning. 

The school has now warned pupils not to use the park when travelling to or from school. 

It has been claimed that a group of students were approached by men in balaclavas armed with a knife, who then demanded their bikes and phones. 

The pupils handed over the bikes. 

An email from the school to parents said: "Please be aware that this morning there was an incident in Admirals Park, a group of students were approached by young men in balaclavas with a knife; who demanded their bikes and phones. 

"The bikes were taken and this incident is being investigated by the police. 

"Please ensure that you consider the safety of your child on the journey to and from school. 

"We would advise that they do not go through Admirals Park at present."