COUNTER-TERRORISM police are investigating the hacking of a rugby league team website which has been replaced with a page featuring Islam extremist views and the message "I love you Isis".

From last night until earlier this morning, Keighley Cougars website showed a black screen with the words "Hacked By Team System DZ" at the top.

The club's chairman has spoken of his shock at what he called the "sinister hi-jacking" of the website by supporters of terror group Islamic State.

"It's sinister what's happened and whatever organisation, wherever it is in the world should be using its own media, not hijacking other people's," said chairman Gary Fawcett.

"And I hope police find out who's done this wherever they are and bring them to account."

A message posted on the club's twitter feed said: "Apologies, the website has been hacked. The developers are working on it. Will let you know when it's back up and running."

A spokesman for West Yorkshire police said they had received a number of calls about the incident.

"We are aware of this incident and have now passed it to our counter-terrorism unit.

"We will work with the club in relation to this and are making enquiries."

A message on the hacked page "to all the population and the government, especially" claims the "State of Islam" is expanding.

The site also features images of fighter jets which it refers to as "warplanes of making America", pictures of the wreckage of "Muslim homes" and graphic impages of people injured in fighting.

Mr Fawcett said a major worry was that thousands of  youngsters and fans who avidly follow the Cougars online might be exposed to some of the horrific pictures now scrolling on its site.

"It is a concern that children might see some of those nightmare images," he said.

Posting on social media, one person claimed a host server had been hacked, leading to 60 other websites featuring the same page.

A resident of Keighley expressed concern over the financial details of those who have used the website.

He posted: "Are the bank details of people who have bought season tickets merchandise etc from the online shop safe?"