SINGAPORE - A Turkish-based hacker group going by the name of "Ayyildiz Tim" has hacked local car dealer Eurokars Group's Mazda website, but the car dealer has defended the security of its customer data collected via the website.

The defaced www.mazda.com.sg website, spotted as early as 9am Thursday morning, carried the hacker group's logo and the message: "Injustice, Oppression and War with all our might...Freedom for All Muslims."

The defaced page was taken down at around 10.30am, replaced by the "Service Temporarily Unavailable" message. But by around 11.15am, the website was up again.

When contacted, a Mazda spokesman confirmed that the site was attacked, but said the car dealer was still investigating the incident. A police report has been made.

The Straits Times understands that the website was down for "a couple of hours".

The Mazda website allows car owners to make service appointments by entering personal details such as name and NRIC, car and contact numbers. It is not known if customer details were compromised. But Mazda's spokesman said: "There is no evidence at present to suggest that customer data have been compromised."

In August last year, the same group reportedly hacked into Israel's Iron Dome air defence system, which can intercept and and destroy short-range rockets, artillery shells and mortars.