Gregory Chelli on Twitter. Photo montage: Tweaktown.

French media are reporting that, apparently, a single Zionist computer hacker is defacing news, and pro-Palestinian websites with pro-Israel messages, and driving the editors of a major publication nuts.

Gregory Chelli, reportedly 32-years-old, and born in Paris’ 16th Arrondisement, goes by the online nickname “Ulcan,” and is a former member of the local Jewish Defense League chapter. As a new immigrant, he now lives in Israel’s coastal city of Ashdod, according to France’s Liberation.

His apparent main target, Rue89, a section of the Le Nouvel Observateur website, and co-founder Pierre Haski, are furious with Chelli:

“Recall the facts and their severity that justified no fewer than five [police] complaints from the site and its employees. Since July 29, the date of publication of the article that displeased him, this pseudo-hacker known as ‘Ulcan’ retaliates with weapons he loves every day: hacking, phone pranks and hacking,” according to the site.

Tech website Tweaktown, in an article on Chelli, quoted Nina Ognianova, a program coordinator for the Committee for the Protection of Journalists Europe and Central Asia:

“We call on French and Israeli authorities to launch a thorough investigation into these attacks on Rue89 and to ensure its staff members’ safety,” Ognianova said.

“Such intimidation tactics against journalists and their families must not be tolerated, lest they lead the media to self-censor,” according to Ognianova.

“Chelli reportedly called… Benoit Le Corre, a journalist responsible for publishing an online profile of Chelli, saying his parents were dead. He also made a phone call to local police posing as Haski, saying he killed his wife and was ready to have a shootout with responding police authorities.”

In a telephone interview with Liberation, Chelli described himself as a “Zionist activist engaged in a fight because Israel has the right to live and to defend itself.”

Defining himself as “not a man of [the] extreme Right, I am not against Islam…” when queried over his hacking exploits, he asserted that,”Israel represents only 0.3% of the territory of the Middle East, we are entitled to this land. I’m not ashamed of what I did,” according to Liberation.