Amnesty International under fire as critics site controversial tweet by campaigns manager as proof of anti-Israel bias.

A senior Amnesty International official is facing angry criticism after comparing Israel with ISIS - on the same day his organization released a report accusing Israel of "war crimes." Israel has rejected that report as "terrorist propaganda," firing that it essentially a regurgitation of Hamas allegations.

On Wednesday Amnesty's UK campaigns manager Kristyan Benedict responded to the Amnesty report by tweeting: “Israeli regimes [sic] response to our Gaza report: Amnesty is ‘a propaganda tool for Hamas & other terror groups’ (#JSIL?)”

The hashtag #JSIL is sometimes used by radical anti-Israel campaigners as a way of comparing Israel to the radical Islamist group.

The UK's Jewish Leadership Council responded to the tweet by saying such blatant bias by a senior Amnesty activist bolstered claims that the organization is pursuing a one-sided agenda against Israel.

"For the campaigns manager of Amnesty International to compare Israel to the Islamic State raises serious concerns about Amnesty’s own partiality and discernment," the JLC said, according to the Jewis Chronicle.

"To impart such a pernicious smear whilst tweeting a link to an article in the Jewish media only serves to increase the offence caused."

It noted that "this is not the first time Kristyan Benedict has shown grave misconduct when carrying out his professional duties. Without internal action being taken, we must seriously question Amnesty International’s sincerity in preventing the misuse of social media by its staff.

"We expect Amnesty International’s staff to comply with their existing, internal guidelines for the use of social media, which would surely consider this comparison beyond the pale."

Benedict has been accused of anti-Israel bias, and even anti-Semitism, in the past.

Following the IDF's previous military operation in Gaza, Operation Pillar of Defense, he posted a tweet targeting three Jewish MPs: "Louise Ellman, Robert Halfon and Luciana Berger walk into a bar…each orders a round of B52s … #Gaza" - a reference to the American bomber and alcoholic drink of the same name.

He has also hosted talks and events by numerous radical anti-Israel campaigners.

Responding to the latest controversy, Amnesty International said that it was "investigating" the tweet for potential misconduct.

"This tweet was made in a personal capacity by a member of staff. It’s being investigated internally. We take issues of social media misuse very seriously."