Police investigating image of Palestinian masked 'gunman' in combat fatigues at Halloween event in Londonderry

The costume features a man in camouflage gear, a fake gun, a green headband with some symbols on it, a mask and a miniature Palestinian flag.

The picture definitely shows a Halloween celebration in Guildhall Square in the city, but it is not clear when it was taken.

Some aspects of the image match the layout of this year’s council-run festivities in Guildhall Square – similar positioning of speakers, similar tent types, and similar banners, for instance.

But other aspects of the image do not appear to match the layout of this year’s event: for example, an ice cream vendor seems to be in a different place in a council photo of the festivities than in the ‘Palestinian man’ photo, and the layout of some of the stalls appears to be different.

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It is not clear either which group the man is purporting to belong to; the green headband he is wearing does not match many common headbands for groups like Hamas, Islamic Jihad, or Hezbollah.

The News Letter has struggled to establish what the Arabic-style script on it means, if indeed it means anything.

The PSNI has issued a statement in the name of the district commander Nigel Goddard, saying: “We are aware of an image posted on social media, and we are working to establish if this is genuine and, if so, when this person was pictured.

“No officer who was on duty in the city centre this week observed this person.

"We understand fully the offence this will cause, and how inappropriate this image is given the events in the Middle East right now. This may also constitute a criminal offence under Section 13 of The Terrorism Act.

"From the image that we have right now, this will clearly be extremely difficult to identify the person pictured.

"Therefore, we would ask anyone who saw this person, can assist in identifying this person, or who may have captured this person on their mobile phone to call us on 101.

"We would also ask the person themselves to contact us to clear this matter up."

Arlene Foster had written on Twitter: “A Halloween festival with kids milling about and someone decides to dress up as a Hamas terrorist.

"Glorifying and normalising terrorism has consequences - none of them good.”

And Jon Burrows, a retired NI police officer wrote: “It’s an offence under s.13 Terrorism Act 2000 to wear clothing that creates a suspicion you support a proscribed organisation - Hamas is proscribed.

"We cannot be a society that tolerates & normalises this behaviour, whatever our politics.”

As to where the image came from, the first mention of it the News Letter can see was at 9.31pm on Tuesday night, when the account Arab Social Nationalist (@ArabSocNat, c.700 followers) tweeted it out, along with the words: “Irish Nationalists do Halloween better. #DerryHalloween #Derry #Hamas @_AnSionnachBan_.”

Arab Socialist Nationalist is an extremely active account, posting continually about the evils of “the Jew”.

Its account bio describes it as “political art and high satire”.

Its recent tweets and retweets involve references to Zionist Occupied Governments (ZOGs – a common term used by people who believe a network of Jews secretly controls much of the world), a reference to “wogs” from an account dedicated to “Australia for the white man”, and denials of the Holocaust.

One of @ArabSocNat’s latest posts, in response to the death of two Israeli soldiers, read: “And yet they still have Hell to look forward to. May they roast eternally, in a grand, perpetual, celestial Auschwitz, masturbated to d*ath by otherworldly nazis.”

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When another Twitter user criticised its image of the ‘gunman’ in Londonderry and called for a police investigation, @ArabSocNat replied: “Whilst one day I certainly do expect that laws against ‘Upsetting the Precious Jews’ may well one day be on the books in the United Kingdom, it’s not yet the case.”

The account @_AnSionnachBan_, mentioned in @ArabSocNat’s original tweet is a tiny account with just a couple of dozen followers which supports the anti-immigrant Irish National Party.

It is also worth noting that software has advanced so far that it is now possible to produce counterfeit images which look indistinguishable from reality, as long as someone has the right app and knowhow – so it is not impossible the image falls into that category.