Police are investigating attempts to compromise the JC website after an attack by a pro-Palestinian hacker.
The site was suspended on Sunday evening after a message was posted on the home page in support of "Palestinian Mujahaeeds".
The perpetrator was believed to have been operating from a computer in Turkey, a country which was involved in a diplomatic row with israel.
No damage was done to the company’s internet operation and the message was removed when the site was briefly suspended from public view.
But staff were inundated with calls, emails and text messages from concerned readers as news spread. News also spread quickly via Twitter, blogs and media journalists.
IT experts at the JC and externally are still examining the site’s security facilites for clues as to how the breach occurred and will pass their findings to specialist officers shortly.
The message, in poor English and repeated in Turkish, was headed: “Hacked by Palestinian Mujaheeds” and complained of Palestinian human rights breaches.
Part of it read clumsily: “Aren’t you ashamed of showing respect to Jewish who makes revenge, hatred and rivality feelings between the people?”
Editor Stephen Pollard earlier dismissed it by saying: “Only those without the confidence to win an argument resort to such tactics. And it was a pretty self-defeating attempt to silence us. Our site was down for a few hours, but as a result we will get more readers than ever before.”
A similar message was placed on the home page of the Israeli site Israelweather.il