Spanish reporter Javier Espinosa, who was held in Syria by the Islamic State, at a news conference upon his return to Madrid last year. (Gabriel Pecot/AP)

Warning: This story contains graphic descriptions of beheadings.

Spanish journalist Javier Espinosa said he remembers the moment the Islamic State militant known as “Jihadi John” slid an antique sword across his throat.

“Feel it? Cold, isn’t it? Can you imagine the pain you’ll feel when it cuts? Unimaginable pain,” Espinosa quoted the terrorist, who was identified last month as Mohammed Emwazi by The Washington Post.

This footage of "Jihadi John" shows his role in the barbaric actions of the Islamic State. (The Washington Post)

Espinosa, a correspondent for the Spanish newspaper El Mundo, was captured alongside freelance photographer Ricardo Garcia Vilanova in September 2013 and held for more than six months in the northern Syrian city Raqqa, the Islamic State’s claimed capital. During that time, he said, Emwazi took the lead in mock executions, a rehearsal for death that leaves hostages wondering whether they will actually die. It happened to Espinosa, and he wrote about it over the weekend for the Sunday Times.

“It was brushing my jugular now,” he wrote in a Sunday Times opinion piece, about the sword against his skin. He remembered Emwazi’s words: “The first hit will sever your veins. The blood mixes with your saliva.”

“The second blow opens your neck,” he quoted Emwazi. “You wouldn’t be able to breathe through your nose at this stage, just your throat. You’d make some amusing guttural sounds — I’ve seen it before, you all squirm like animals, like pigs. The third blow will take off your head. I’d put in on your back.”

Then, Espinosa said, the militant exchanged the sword for a pistol, pressed it into Espinosa’s head and pulled the trigger three times. “Click. Click. Click,” he wrote.

Espinosa published a similar account on Sunday in El Mundo.

[‘Jihadi John’ is a Kuwaiti-born Londoner named Mohammed Emwazi]

Espinosa has been a Middle East correspondent for El Mundo for about 13 years. In September 2013, he and Vilanova were wrapping up a two-week reporting trip, El Mundo said at the time, when they were captured by Islamic State militants near the Turkish border, according to BBC News. Espinosa was ultimately taken to a house near Tabka, a town about 35 miles from Raqqa.

“‘What sort of journalist are you? A war reporter?’ asked a young militant in perfect English,” Espinosa wrote. ” ‘We don’t like journalists. They always lie.’ ”

Over the next six months, psychological torment became routine for Espinosa and 23 other captives the Islamic State was holding in Syria.

[Why did victims in Islamic State beheading videos look so calm? They didn’t know it was real.]

When the hostages themselves didn’t seem terrified enough for their own lives, the militants reportedly threatened to kill fellow prisoners.

“The hooded militants turned their attention to Ricardo, a Spaniard like me,” Espinosa wrote in the Sunday Times. “He was kneeling, blindfolded in a corner of the room. John [Emwazi] told his companion to point his Kalashnikov [rifle] at Ricardo’s head.

“‘Would you prefer it if we shot your friend,’ he shouted. ‘Do you want to be responsible for his death?’

“If I had doubted it before, this encounter confirmed the psychopathic character of our interrogators.”

Foreign policy reporter Adam Goldman explains who Mohammed Emwazi is and how The Washington Post discovered his identity. (Gillian Brockell and Alice Li/The Washington Post)

The hostages called their three English captors the “Beatles,” a reference to the British rock band with John Lennon. That’s where “Jihadi John” got his nickname, since he “loved this sort of theatre,” Espinosa wrote.

Emwazi, 26, was born in Kuwait and raised in West London. In 2009, he graduated from the University of Westminster with a computer science degree. His friends told The Post he was a polite and quiet man — a far cry from the ruthless jihadist who has apparently beheaded American, British and Japanese hostages on film.

[The futile and frustrating efforts to save Kayla Mueller]

Several of Espinosa’s fellow prisoners were executed.

Most Islamic State’s beheading videos start the same — a British militant stands near a hostage clad in a orange jumpsuit kneeling in the desert. The captive spouts a jihadist propaganda script. Then the militant decapitates him. So far, the Islamic State has killed three Americans, two British and two Japanese hostages on video. Aid worker Kayla Mueller, 26, was reportedly killed in a Jordanian airstrike, though the United States wasn’t able to verify it.

Strangely, most victims in the videos seemed calm. An Islamic State defector told Sky News that’s because the hostages had been through mock executions. They didn’t know they were about to be killed.

Also, Espinosa said, he was forced to stare at a gruesome photo of Russian engineer Sergei Gorbunov, who shared a prison cell with him before he was murdered.

“ ‘What do you see in the photo? Tell the others!’ shouted the Beatle we called George,” Espinosa wrote in the Sunday Times. “He wanted me to describe the picture they had taken of Sergei after killing him.

“ ‘The sheikh shot him with an explosive bullet,’ said this crazed individual in an admiring tone, forcing me to look at his laptop. ‘Tell me, what do you see?’ he shrieked.

“ ‘I see Sergei, he’s dead, there’s blood, bits of brain on his beard,’ I replied.

“’Yes, and don’t you see the enormous hole made by the bullet,’ he replied exultantly. ‘You might end up with him. We’ll make you dig him up and put you in another tomb where you can sleep with him.’ ”

Espinosa said in his opinion piece that “only now” can he share his whole story because “the militants had threatened to murder hostages if we said anything in the media ‘before it’s all over.’ ”

Espinosa is now based in Beirut.

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