An in-house photomontage of Assange with the fake tweet, using an original photo from Getty.

The United States has The Onion, the United Kingdom has The Daily Mash. And Spain too has a top-class satirical website, El Mundo Today, which, like its foreign counterparts, has managed to hoodwink celebrities more than a few times into believing that its comic takes on current affairs are actually real stories.

Its coverage of the ongoing crisis in Catalonia, for example, has just managed to dupe Julian Assange, the WikiLeaks founder who has been regularly weighing in on the independence drive in the northeastern Spanish region, and siding firmly with the pro-secessionist forces.

The El Mundo Today story in question stated that Assange had started to “tweet random words in Catalan to support the protestors.” The mocked-up tweet put together by the publication included part of a tongue twister (setze jutges), and the words fuet (Catalan cured sausage), Barça (as in the soccer club), collons (balls) and renoi (damn it).

Assange took the story to be serious and responded writing in Spanish: “False. El Mundo, the stupid. Today, tomorrow, always.” He later deleted his response, but other Twitter users took screen grabs, which have been widely shared online since. El Mundo Today also deleted its response, which read in Catalan “què t’empatolles, marrec,” which could be roughly translated as, “What are you moaning about dude?”

Someone quickly pointed out to Assange that El Mundo Today is a satirical publication, to which the Australian WikiLeaks founder replied: “I appreciate the joke. But it’s hard to tell the difference with the real “El Mundo” which is often ferociously stupid,” in reference to the Spanish daily.

Assange has been getting involved in the debate over the referendum in Catalonia – via Twitter, at least, given that he has been confined to the Ecuadorian embassy in London since 2012, after a British court approved his extradition to Sweden over two accusations of rape and sexual abuse. The investigation was shelved in May, but an arrest warrant is still out for him in the UK for not having appeared to testify in court.

In a previous tweet, posted on September 10, Assange stated that “Catalonia, like Pancho Sanchez, will not tolerate being abused forever.” Twitter users were quickly asking themselves (in one case via a survey) whether he was referring to Mexican Revolutionary general Pancho Villa or Don Quixote character Sancho Panza. Or indeed whether he was referring to Socialist Party leader Pedro Sánchez. Once again, Assange deleted the tweet.

He has also claimed via Twitter that “Spain could block the entire internet” to prevent the Catalan independence vote from going ahead, something that in practice would be impossible. He also waded into an online spat over Catalonia with Spanish journalist and author Arturo Pérez-Reverte, who at one point in the conversation called the WikiLeaks founder “a perfect idiot.”

Despite these slip-ups, many backers of the referendum have gratefully received Assange’s support for the planned vote, and his criticism of the handling of the situation by the Spanish central government of Prime Minister Mariano Rajoy.