An ISIS jihadi poses for a chilling photo next to holidaymakers on the beach at a resort in Turkey.

Raising fears that that terror group is planning another Tunisia-style beach massacre, jihadist Pasaliasi Isde stood next to unsuspecting holidaymakers at the Black Sea resort of Amasra.

The new photos were posted on Facebook yesterday. Isde also used Facebook to 'check in' to a number of beach resorts along the coast in the last fortnight.

One million British holidaymakers visit Turkey every year, the Association of British Travel Agents said today.

Jihadi holiday: Clean-shaven and in his swimming trunks, ISIS fighter is pictured next to the beach at the Black Sea resort of Amara in Turkey

Sunning himself: Terror soldier Isde takes a selfie on a popular holiday resort in Turkey. He has also Facebook to 'check in' on the Black Sea beaches of Bartin and Amasra in recent days

Dark secret: The beach snaps are in stark contrast to his day job when Isde poses on the back of a truck next to a rocket launcher and an Islamic State flag in northern Syria

Gruesome: Isme's beach images are in stark contrast to Isde's activities over the border in Syria in recent months - where he happily posed alongside mutilated corpses and severed heads

Clean-shaven and wearing Western-style clothing, the photographs are in stark contrast to Isde's activities over the border in Syria in recent months - where he happily posed alongside mutilated corpses and severed heads while fighting under the sinister black banner of the Islamic State.

His Facebook page, which has now been deleted, showed how he promotes extremist propaganda lauding the activities of the Islamic State and urging friends to behead Westerners.

Posing alongside well known jihadis in war torn areas of Syria, a bearded Isde is seen dressed in military fatigues and holding assault rifles alongside the terror group's chilling black banner.

Images that appear to have been taken on a mobile phone show a row of severed heads of three Syrian regime soldiers, suggesting Isde witnessed or possibly even participated in their murders.

Elsewhere Isde urged his Facebook friends to 'cut of the heads of the Kuffar [non-believers]' and issued the stark threat: 'You are either with us or against us'.

He also celebrated ISIS' leader Abu Bakr al-Baghdadi in a series of photographs, leaving viewers with no doubt where his allegiances lie.

Holidaymakers in Turkey he mingled with this week would have been completely oblivious to the depraved mindset of the now clean-shaven, Western-dressed man taking selfies near them as they sat on the beach.

Popular: A harrowing sequence of images show Isde smiling as he takes a selfie in the sunshine surrounded by holidaymakers enjoying a summer break on the Black Sea

Isde is seen wearing military fatigues and holding assault rifles while raising his index finger in a jihadi gesture

The Turkish ISIS fighter recently posted this picture on Facebook, showing him posing with a gun next to a signpost marking out the direction of several northern Syrian towns

In a chilling twist, Isde's Facebook page was not discovered by Turkish security officials but by Macer Gifford - a British national who gave up a top job in the City last December to fight alongside the brave Kurdish forces battling ISIS in Syria and Iraq.

Macer - his nom de guerre - alerted MailOnline as Isde pulled down the pictures on his Facebook page.

Speaking exclusively to MailOnline, he said: 'This is every family's worst nightmare. After the events in Tunisia people need to be aware of the global nature of the ISIS threat.

'Its chilling to see someone that has fought alongside ISIS in Syria, smiling and relaxing next holidaymakers.'

'These images will at best be humiliating for the Turkish authorities. At worst it confirms allegations Turkey is allowing ISIS fighters to operate within its borders.'

'Let's be absolutely clear, Turkey is a wealthy country with a very effective security apparatus. How is it that I can track these people down online from the UK and Turkey can't?'

The Foreign Office said today it doesn't comment on specific terror threats - but advised British holidaymakers to check travel advice on the FCO website before travelling.

A note on the FCO page reads: ‘There is a high threat from terrorism in Turkey and there are active terrorist groups throughout the country. These include domestic religious extremist and ideological groups, and international groups involved in the conflict in Syria. Attacks could be indiscriminate and could affect places visited by foreigners.’

In June 38 holidaymakers were killed - 30 of them British - when Tunisian ISIS gunman Seifeddine Rezgui opened fire on a beach in Sousse.

The Foreign Office ordered Brit holidaymakers home a fortnight later when they said that a second terror attack was imminent.

On his Facebook page, Isde urged his Facebook friends to 'cut of the heads of the Kuffar [non-believers]' and issues the stark threat: 'You are either with us or against us'

Extremist: Isde is seen wearing military fatigues in a recent photograph posted on his Facebook page

Location: The images show Isde taking selfies and using Facebook to 'check in' on the Black Sea beaches of Bartin and Amasra - resorts visited by thousands of families every year

The harrowing images emerged as Turkish warplanes bombed ISIS positions inside Syria for the first time overnight in a dramatic escalation of fighting after the killing of a Turkish soldier in cross-border clashes.

Three F-16s took off from the southern city of Diyarbakir for an early morning bombing raid against three ISIS targets, dropping four guided bombs, a statement from the prime minister's office said.

Just hours earlier the first major cross-border clashes between Turkey and ISIS took place, leaving one soldier and one militant dead and thrusting Turkey into an open conflict with the jihadis.

And on Monday a suspected ISIS suicide bomber killed 32 anti-ISIS activists in the southern Turkish city of Suruc while they were on a trip to raise awareness of the Syrian city of Kobane.

The fighting erupted after the killing of 32 people in a suicide bombing Monday in a Turkish town on the Syrian border that the government blamed on ISIS.

This sparked an upsurge in violence in Turkey's Kurdish-dominated southeast, where many accuse the Turkish authorities of collaborating with the terror group - accusations Ankara denies.

This morning Turkish police launched raids to arrest suspected ISIS members and Kurdish militants in an apparent bid to stamp down on all sources of violence, the official Anatolia news agency said.