When two Sicilian women shared a kiss on 26 April, they kickstarted a “selfie-guerrilla’’ photobomb protest against Italy’s far-right deputy prime minister, Matteo Salvini.

Matilde Rizzo and Gaia Parisi, both 19, approached Salvini, the leader of the League, for a selfie after a rally in Caltanissetta, Sicily. While Salvini was preparing to smile for the photo, the trap was set by the two young women who kissed in front of the camera.

“We were going to Caltanissetta to protest against Salvini and his dangerous anti-abortion and sovereign propaganda,” said Rizzo, a chemical engineering student in Turin. “At the end of the meeting, Salvini announced to the audience his willingness to meet his supporters and pose with them for selfies. I looked at Gaia and we didn’t think twice about it.”

The kiss was a protest against Salvini, who had endorsed the anti-LGBT, anti-feminist and anti-abortion World Congress of Families (WCF), held in Verona in March.

Women photobomb Matteo Salvini with same-sex kiss Read more

Rizzo said: “His presence at an anti-feminist, anti-gay and anti-abortion congress was unacceptable. We could not stand by and watch as Salvini and his supporters tried to drag Italy back into the middle ages.”

After the photobomb, Parisi and Rizzo both posted the image to their Instagram and Facebook pages. The selfie went viral, with millions of shares worldwide.

“The photo was circulated around the world. We were proud. We had achieved our goal, we made ourselves heard and this is important,” said Rizzo.

That same evening, at a rally in the Sicilian city of Gela, Salvini responded to the joke, saying: “They thought they had got one over on me. I was pleased. I don’t care at all if a girl wants to make love with another girl as long as the mother and father are not erased.”

Others have also taken advantage of the minister’s habit of posing for selfies and video-selfies with his fans. In February, a 15-year-old boy from Sardinia approached the minister and recorded a video-selfie in which he asked the minister about allegations that the League had stolen €49m (£42m) from the Italian state. Salvini walked away.

Since Rizzo and Parisi’s kiss, photobombs and jokes have increased each day and the Italian newspapers have described the phenomenon as a “selfie guerrilla” campaign against the minister.

“Someone has found a way to turn Salvini’s secret popularity weapon against him, giving us something to laugh at,’’ wrote Maurizio Crippa in the newspaper Il Foglio.

After a rally on Thursday, a boy from the province of Pesaro in the Adriatic tried to kiss Salvini while two girls exchanged a kiss.

Three days earlier, a woman from Salerno, a port city south-east of Naples, asked Salvini in a video-selfie if southern Italians were still “terroni”, a derogatory term that originally meant “farmer” and is used by League supporters against southerners.

“Delete this video,” Salvini told the woman. The minister then asked the police to intervene and seize her mobile phone. Some agents carried out the minister’s orders but later the phone was returned to her and the video went viral once again.