A 24-year-old man who died after he was found seriously injured at a house in Hertfordshire had been stabbed, police said. [16 July 2012]

Darren Leonard was discovered at 11.30pm on Wednesday after police were called to reports of a disturbance at an address in the Northfield area of Hatfield.

Ambulance crews were also called to the property and Mr Leonard was taken to Lister Hospital in Stevenage, but died shortly afterwards.

A spokeswoman for Hertfordshire Police said a post-mortem examination carried out on Thursday afternoon revealed he died as a result of stab wounds.

Detective Chief Inspector Martin Brunning, from the Bedfordshire, Cambridgeshire and Hertfordshire Major Crime Unit, said: "We are determined to catch the people who killed Darren and will leave no stone unturned in order to find them.

"We are keen to speak to anyone who has information about this incident.

If you saw anything unusual on Wednesday evening through into the early hours of Thursday morning in that area, please get in touch with the Operation Bulrush team by calling 101."

The force spokeswoman said a significant murder inquiry is under way.

Police have been carrying out house-to-house inquiries in the Northfield area and monitoring CCTV footage from local cameras, among other lines of investigation.

The force spokeswoman added: "Police are aware that there has been considerable speculation on social media websites and within the Hatfield community because of the concerning nature of this incident.

"As a result, officers have been conducting extra patrols in the Birchwood area to offer reassurance to local residents who have concerns."

Anyone with information should contact police on the non-emergency number 101. Alternatively, call Crimestoppers, the independent charity, anonymously on 0800 555 111.

Crimestoppers is an independent charity and not part of the police. If you wish to pass on information about crime anonymously, please call Crimestoppers on 0800 555 111, or fill out our anonymous online Giving Information Form.