Huge numbers of people have turned out at pro-Palestinian rallies across Europe, calling for an immediate end to the war in Gaza and the release of activists on board a flotilla carrying humanitarian aid to the territory.

Police in Rome said about 250,000 people attended a fourth consecutive day of protests on Saturday after Israel intercepted the 45-boat flotilla trying to reach Gaza last week.

Protesters in the Italian capital, including families with children, shouted: “We are all Palestinians,” “Free Palestine” and “Stop the genocide” as many carried Palestinian flags and wore black-and-white-chequered keffiyehs.

In Spain, about 70,000 people took to the streets in Barcelona, according to the police, while the government in Madrid reported nearly 92,000 marched in the capital.

The Global Sumud Flotilla, which was intercepted on Wednesday, departed Barcelona in early September and had been seeking to break the Israeli blockade of Gaza, where a United Nations-backed hunger monitor says famine has taken hold. About 50 Spaniards on the flotilla have been detained by Israel, Spanish Foreign Minister Jose Manuel Albares told public television in an interview broadcast on Saturday.

Marta Carranza, a 65-year-old pensioner demonstrating in Barcelona with a Palestinian flag on her back, said Israel’s policy “has been wrong for many years and we have to take to the streets”.

Elsewhere, several thousand people marched through the centre of Dublin to mark what organisers described as “two years of genocide” in Gaza. Along with Ireland, Spain is among the fiercest European critics of Israel’s military offensive in Gaza.

In Ireland, speakers called for sanctions on Israel, an immediate end to the conflict and Palestinian involvement in any ceasefire plan.

In London, police said they made at least 442 arrests at a gathering in support of the proscribed Palestine Action group.

In Paris, where about 10,000 people gathered, a spokesperson for the French contingent of the Sumud Flotilla, Helene Coron, told the crowd: “We’ll never stop.”

“This flotilla didn’t get to Gaza. But we will send another, then another until Palestine and Gaza are free,” she said.

In Italy, Prime Minister Giorgia Meloni’s right-wing government has been criticised for its inaction regarding the siege of Gaza. On Saturday, Meloni accused demonstrators of defacing a statue of Pope John Paul II with graffiti in front of Rome’s main railway station, calling it a “shameful act”.

On September 14, about 100,000 pro-Palestinian demonstrators forced the final stage of the Vuelta a Espana cycling race in the Spanish capital to be halted because an Israeli team was competing. Prime Minister Pedro Sanchez said Israel should be barred from international sport over the war in Gaza, just as Russia has been penalised over its invasion of Ukraine.

In September, Spain announced it would ban imports from Israeli settlements in the occupied West Bank, which are illegal under international law.