A police officer was stabbed when a water fight which broke out during the hottest day of the year turned nasty.

The incident happened near the Serpentine in Hyde Park on Tuesday (July 19) evening and saw a second police officer also injured when they were hit by one of the bottles thrown towards officers.

In total five officers were hurt as the crowd grew to around 2,000 people.

Police had been at the scene since around 3pm after a large number of people gathered for a spontaneous ‘water fight’.

Police say things turned violent at around 8.40pm when some of the crowd tried to set up a sound system. The increasingly large gathering become hostile to police and items - including bottles - were thrown towards officers wearing riot gear.

The officers who suffered a stab wound and was struck by the bottle were taken to hospital for treatment with injuries described as not life threatening.

Two other people also suffered stab wounds and were taken to hospital. One has injuries described as not life threatening, while an update on the second is yet to be given. A third member of the public was injured.

Other officers remained at Hyde Park dealing with the incident until the crowds had been dispersed by around 2.20am on Wednesday (July 20).

An investigation has been launched but there have been no arrests at this time.

Commander BJ Harrington said: “What took place wasn’t a group of people out enjoying the sunshine, but crime and disorder which is quite simply unacceptable. Officers are out and about on duty today and we want everyone in London to have a safe and enjoyable day.

“We are now running a post event investigation. I know that there is a lot of footage available, including helicopter footage and CCTV.

“If you have any footage that may help, or any information, then please get in touch with us.”

And he also warned: “If people are going to go along to unlicensed or spontaneous events then please think very carefully, they are simply not safe.”

Any witnesses or anyone with information regarding this incident is asked to call police in Westminster via 101. To give information anonymously contact Crimestoppers on 0800 555 111 or at crimestoppers-uk.org.