ROSARIO, Argentina – Despite restrictions on hate speech on social media in Spain, a trending hashtag calling for Catholic priests to be burned alive was not removed for violating rules against posting calls for violence.

The invitation to #FuegoAlClero, or set fire to the clergy, was first issued by several pro-Marxist accounts, originally in defense of a bill to reform Spain’s education system that would put the state in control of religious instruction in public schools and limit support for thousands of Catholic schools, which could lead to their closure.

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However, the trending topic was accompanied by calls to burn down churches because “the only church that illuminates is the one that is in flames,” signed by “the daughters of the witches you couldn’t burn.”

By Tuesday evening, Twitter had done nothing about the tweets, despite thousands of users complaining the hashtag was inciting hatred and a direct violation of the company’s rules against “violence, harassment and other similar types of behavior.”

In particular, Twitter’s regulations state that users cannot “threaten violence against an individual or a group of people.” The glorification of violence is also banned, as is the use of the social media platform to promote violent extremism, harassment or hateful conduct on the basis of religious affiliation.

The “Celaa Law” – the bill to reform Spain’s education system named for the Spanish minister of education, Isabel Celaa – passed its first hurdle last week, and is expected to become a law despite the lack of support from education institutions.

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In addition to its effect on religious education, the proposed law also calls for the closure of specialist schools that serve children with physical or mental disabilities in order to “mainstream” them at the schools that serve the general population, despite strong opposition from experts and the parents of special needs children.

The bishops are not the only ones to oppose the Celaa Law: Employers, unions and parents came together to form “Mas Plurales,” a platform that calls for real plurality in the Spanish educational system.

Hundreds of thousand rallied last Sunday against the proposed law, yet the Socialist government argues that those who defend mostly Catholic private education – that serves two million children and that has thousands of institutions – are actually defending a state-financed educational system marked by “segregating elitism and privilege.”

“We ask for a political pact to produce a law that represents the entire educational community and the entire society,” said Brother Pedro Huerta, general secretary of Catholic Schools, on Sunday.

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He was speaking from a rally in Madrid’s downtown Plaza de Cibeles. He’s quoted by Vida Nueva calling the protest a “peaceful tide that demands rights, but above all, [demands] to be heard.”

Huerta defined the concerted schools system, privately ran but with partial federal funding, as “a plural integrating model in which everyone fits,” and regretted that the proposed reform “seeks to portray our schools as unfair, when this is false.”

An estimated 30 percent of Spain’s children attend these concerted education schools, savin the state over five billion dollars.

He said the government is not “subsidizing institutions, but people, families,” and families have a right to “continue defending freedom of education.”

On Saturday, Cardinal Juan Jose Omella of Barcelona, the president of the Spanish bishops conference, wrote an op-ed in La Vanguardia, saying that “the clamor of the vast majority of society for an educational pact in Spain – which is long-term and incorporates all political forces and also civil and religious entities active in the field of education – has not stopped growing.”

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He argued that the Church’s work in education in Spain reaches almost two million families, many of them in the poorest areas of the country.

“We work like other institutions to promote the human and integral development of each person,” the cardinal argued. “That is why we deeply regret all the obstacles that they want to impose on the action of [state-supported] Catholic institutions.”

“This is not the time to put obstacles, to confront public and private institutions, but to work together, to cooperate effectively and efficiently to offer an adequate education to all children, adolescents and young people in our country, respecting the constitutional right of fathers and mothers to freely choose the center and the educational model for their children, and always ensuring the constitutional right to free private initiative,” Omella wrote.

Follow Inés San Martín on Twitter: @inesanma