Violence in Syria continues to rage as security forces killed more than 50 protesters in the city of Hom today. With the death toll for the past six days totaling over 400, Arab League ministers are exploring a new proposal to send a joint U.N-Arab League mission to Syria.

“There is a proposal from the secretary-general of the Arab League to form a joint mission for Syria in coordination with the United Nations, and it will be presented before the planned Arab foreign ministers’ meeting on Sunday in Cairo,” the Arab League’s deputy head, Ahmed Ben Helli, told reporters today.

The upcoming ministerial meeting in Cairo may also issue a statement on China and Russia’s veto of a U.N. Security Council Resolution last Saturday, reports Reuters. The resolution was based on an Arab peace plan that had the support of the rest of the Security Council but China and Russia’s veto brought criticism from both Western and Arab nations.

The ongoing artillery bombardment of Homs, a recently leaked report detailing the failures of an Arab League observer mission, and the Russian and Chinese veto have left the Arab League and the United Nations looking for new strategies to halt the bloodshed.

Arab League Secretary-General Nabil Elaraby announced this week that a new mission would need international backing, better equipment and more observers than the Arab League mission. Yesterday, U.N. Secretary-General Ban Ki-moon confirmed that Elaraby had proposed a joint mission.

Consultations will be held with the Arab League and Security Council members “before fleshing out the details,” said the U.N. chief. But Western powers offered a lukewarm response to the proposal. Agence France-Presse reports that France said there would have to be “guarantees” for the mission and Germany called it a “very serious” idea but emphasized that conditions would have to be met before such an effort could be launched.

While diplomats discuss what steps to take next, Human Rights Watch (HRW) urged the Syrian government to stop shelling residential areas of Homs. “Those responsible for such horrific attacks will have to answer for them,” HRW’s Anna Neistat in a statement earlier today.

Rights groups estimate that more than 6,000 people have died since protests began eleven months ago.

An exclusive report by NBC News cites two U.S. officials confirming links between an assassination campaign against Iranian scientists and an Iranian exile group designated as a foreign terror organization by the State Department since 1997. Two officials confirmed to NBC that the group, the Paris- and Iraq-based Mujahedeen-e Khalq (MEK), was involved in the assassinations of Iranian nuclear scientists.

The State Department designates the MEK as a “foreign terrorist organization,” though the group’s supporters have mounted an aggressive lobbying effort aimed at getting delisted through claims it laid down arms in the early 2000s.

The NBC story cited two U.S. officials linking the MEK to the recent spate of assassinations, and a third who neither confirmed nor denied the allegation:

Two senior U.S. officials confirmed for NBC News the MEK’s role in the assassinations, with one senior official saying, “All your inclinations are correct.” A third official would not confirm or deny the relationship, saying only, “It hasn’t been clearly confirmed yet.” All the officials denied any U.S. involvement in the assassinations.

The group, through its political wing (which was also added to the State designation), denied any involvement in the latest attacks. A “representative” of the group in Washington also denied involvement.

The NBC report also claimed that Israeli intelligence services “financed, trained and armed” the MEK, though the story did not go on to substantiate any direct links between the Israeli government and the assassination campaign.

The U.S. denial of involvement last month, after the latest killing by a bomb blast in Tehran, was unequivocal: “I want to categorically deny any United States involvement in any kind of act of violence inside Iran,” said Secretary of State Hillary Clinton, condemning the attacks.

Founded in the mid-1960s as an armed revolutionary group, the MEK fought against the Shah and his U.S. backers — allegedly killing Americans — in the 1970s, but then split with Iran’s clerical leadership in the early 1980s. Eventually, the group ended up based in Paris and Iraq, where, from the latter location, it was helped by Saddam Hussein to raise arms against Iran during the war between the two countries. Since 1997, when such designations were introduced, the MEK has been considered a “foreign terrorist organization” by the State Department. As many as 3,400 members of the group, which it claims are former fighters who laid down their arms in the early 2000s, are still based in Iraq.

On Tuesday, ThinkProgress reported on the discovery by Demographics United that the Islamophobic filmmakers at the Clarion Fund sent an e-mail newsletter promoting a quote from a reader that attempted to legitimate the views of anti-Muslim Norwegian mass murderer Anders Breivik.

In the 1,500-page manifesto he wrote before slaughtering 77 people, Breivik, who appeared in court this week, recommended a Clarion Film for “further study” about Islam. The reader in the newsletter, whom Clarion claimed was writing from Norway, both whitewashed Breivik’s worldview — falsely suggesting his opposition was only to “Islamist terrorism” rather than to the religion Islam in general — and seemed to claim that a new report from Norway’s security agencies vindicated the mass-killer’s views.

As of yesterday, the comment by the “reader in Norway” no longer appeared on the Clarion site, www.radicalislam.org. The entire newsletter, which used to be available on the web by clicking on a link in the e-mail, now takes viewers to a Clarion page that reads: “The requested page could not be found” (pictured above right). Reached on his cellphone, Clarion official Alex Traiman declined to comment to repeated questions about the newsletter and its disappearance from the web.

Here’s a screen shot of the relevant part of the newsletter, where the “reader from Norway” was quoted in a section called “U Report,” which solicits reader comments and explicitly reviews them before publication:

The full now-scrubbed newsletter, as it was available on the web Tuesday, can be found at the Google cache for the webpage (for now; these tend to disappear after a while) or by downloading a PDF file of the page captured by ThinkProgress.

Last month, the New York Times wrote a story about the Clarion Fund’s film “The Third Jihad” being shown at the registration area of an NYPD conference. Subsequently, and after some dissembling, NYPD commissioner Raymond Kelly apologized for his appearance in the film and labeled it “inflammatory.” New York City mayor Michael Bloomberg slammed the NYPD for showing the film. At that time that controversy broke, ThinkProgress released the most comprehensive list to date of donors to the Clarion Fund.