Leftist NGOs, journalists, may have gone too far in attacking IDF's operation to defend civilians from Gaza rocket attacks.

Left-wing newspaper Haaretz decried Friday what it called a "witch hunt" against leftists and civil rights organisations after the director of the national service administration, Sar-Shalom Jerbi, informed far-left NGO B'Tselem it was being blacklisted as an employer.

"I feel obligated to exercise my power and stop the state assistance provided to an organisation that works against the state and against soldiers who are heroically giving their very lives to protect the safety and well-being of all citizens," Jerbi wrote in a letter.

He accused B'Tselem of disseminating lies and slander, endangering the state and publishing information that encourages Israel's enemies and leads to violent anti-Semitic acts against Jews around the world.

The NGO, which models itself as a "rights group" but which is regularly involved in provocations against Jews in Judea and Samaria, denounced the move as an attack on Israeli democracy, and asked supporters to sign an online petition to support freedom of expression and democracy.

B'Tselem gained notoriety after it was among a number of radical-left NGOs which contributed to the UN's 2009 Goldstone Report, which accused Israel of "war crimes" after Operation Cast Lead. The report was slammed by Israel and other observers as biased, and the report's author, Richard Goldstone, later retracted his most inflammatory claim, that the IDF had deliberately targeted civilians in Gaza.

B'Tselem has maintained a similar stance throughout the recent military operation, drawing widespread resentment.

Israeli public opinion has overwhelmingly supported Operation Protective Edge, which was launched over a month ago to end indiscriminate rocket fire from Gazan terrorists against Israeli civilians. A poll carried out by The Israel Democracy Institute last month said 95 percent of Israeli Jews believed the offensive was just.

Only a few fringe groups from the Israeli left have voiced opposition to the operation, including radical Haaretz journalist Gidon Levy, who accused air force pilots of perpetrating "the cruelest (and) most despicable deeds", despite going through great pains to avoid civilian casualties.

Haaretz itself has suffered as a result of Levy's pieces, which have been considered beyond the pale even by the paper's left-wing readership, and hundreds of readers have cancelled their subscriptions. The paper hired Levy bodyguards after people stopped in the street to insult him and government whip Yariv Levin denounced him as a liar, a "mouthpiece of the enemy" who should be put on trial for treason.

"I have never faced such aggressive reaction, never," Levy told AFP in his cramped office at Haaretz in Tel Aviv, away from the coffee shops where he fears being insulted.