OXFORD'S Hinksey Pool is set to remain closed indefinitely as the council waits to see what turned the water purple.

Experts had hoped to have the results of tests on samples of water from the outdoor swimming pool off Abingdon Road last Wednesday.

But lab technicians still do not know what chemical or substance was put into the water on Friday, August 10.

Steve Holt, leisure operations manager at Oxford City Council, said yesterday: "We are still waiting for the test results to come back from the laboratory.

"Before we can reopen the pool we have a duty to find out what was put in the water to colour it.

"And we need to make sure that even small traces of the substance will not be harmful to customers.

"The pool will remain closed until we receive the results."

He added: "From my own knowledge it could be potassium permanganate - but that is only my own thought. We really don't know what it is. Nothing has been ruled out."

Police investigating the incident are yet to arrest anyone in connection with the crime and are keen to talk to anyone who was in the area on the evening it happened who may have witnessed any suspicious behaviour.

Oscar Van-Nooijen, Hinksey Park ward councillor, said he was frustrated there was still no clear idea what had been used to dye the pool.

He said: "It is very frustrating. As soon as I talked to the staff at the pool it became apparent it was not going to be a case of cleaning it and then reopening the next day.

"It means the council cannot give a 'guestimate' on when it is going to open - which is deeply frustrating for everyone who lives in the area and also bad news for the council because they are losing money. It is bad all round."

On a hot day, the pool nets the council around £2,000, with up to a thousand people coming for a splash.

Mr Van Nooijen added: "It is a pool that thousands of people use at this time of year.

"People are really annoyed both at the idea that someone could do something like this to a local facility, and be so thoughtless about the long-term consequences.

"The area around Hinksey Park was particularly badly hit by the flooding so it is a double whammy for the families to know they cannot use the pool.

"And there are only about two weeks of the summer holidays left."

The pool vandalism was the latest in a spate of attacks on leisure facilities in the area, with the Splash facility next to the pool damaged on Saturday, July 28.

Mr Van Nooijen said patrols by police officers and council staff had been stepped up as a result of the attack but they were yet to catch anyone.

Anyone with information about the vandals is asked to contact police on 08458 505505.