A murder investigation has been launched after a 16-year-old boy died following an assault in Chelmsford last night (February 12), Essex Police has announced.

Police say the boy sustained 'serious injuries' following an assault, on a green space off Waterson Vale at around 11.30pm. He died in hospital.

Within two hours of the report being made, officers arrested an 18-year-old man on suspicion of murder. He remains in custody.

Detective Superintendent Rob Kirby, Head of Major Crime, said: "This is a shocking incident leading to the death of a young boy and I understand that many will be concerned after waking up to this news.

"We are confident that this is an isolated and targeted assault.

"The specialist teams are likely to remain in the area for the next couple of days in order to continue gathering crucial evidence.

"We are continuing to appeal to anyone who was in the area of Waterson Vale or surround roads in Chelmsford last night and may have witnessed or heard anything to contact us. Additionally, anyone with any further information is asked to get in touch. We have launched a Major Incident Public Portal, meaning the public can submit information online, directly to the investigation team."

An Essex Police officer stood next to a police car on Waterson Vale. (Photo: Essex Police)

Specialist officers, including detectives from Essex Police's Serious Crime Directorate and forensic officers, remain at the scene, where a cordon has been put in place while enquiries continue.

Police are urging anybody with information or CCTV, dash cam or other footage in relation to this incident to get in touch. The public can do so by submitting information through the dedicated major incident reporting portal or by calling 101.

Those who would like to make an anonymous report can contact Crimestoppers, by visiting their website or by calling 0800 555 111.