Jose Manuel Villarejo, who was at the time a senior officer in Spain’s National Police Corps, has made a startling allegation: he claimed Wednesday that the vehicular attack in Barcelona on Aug. 17, 2017, was staged by the country’s National Intelligence Service (CNI) in order to discourage Catalonians from voting for independence in a referendum that was then upcoming.

The attack was horrifying. A man named Younes Abouyaaqoub drove a van into a crowd of people on La Rambla in Barcelona, murdering 13 and injuring at least 130. According to Scotland’s The National, “five members of the jihadist cell launched a knife attack on the beachfront at Cambrils, having driven there the day after the Barcelona attack. All five men were shot dead by police. Three men who helped in the attacks were last year sentenced to jail terms of between eight and 53 years. It later emerged that the alleged mastermind of the attacks, an imam in the city of Ripoll, was a CNI informant.”

Despite the attack and the threat of instability it brought, Catalonia voted overwhelmingly for independence anyway. However, its bid for independence was ultimately declared void under heavy pressure from the Spanish government.

Was that government tied to the Barcelona attack by more than just an informant? Villarejo, who participated in many “secret” CNI operations, said that the attack was a brainchild of the agency, in “a bid to destabilise Catalonia” so that the Spanish province would vote against independence. Villarejo asserted that the attacks were conceived by the former director of the CNI, Félix Sanz Roldán, but “were a serious mistake.” Sanz Roldán, said Villarejo, “wanted to give Catalonia a fright, but miscalculated the consequences.”

Villarejo declared that he had documentary proof of his charges. “All the evidence is in my archives. I authorize their release. We must think that the citizenry is not a minor and the law of secrets cannot be used to hide everything. It is an obsolete Francoist law from 1968” that keeps such state documents from being released, he said.

Catalan President Pere Aragonès reacted angrily to Villarejo’s allegations, saying that the Barcelona attack was “a barbarity that has marked us forever. And if Villarejo’s words are true, explanations are needed now. We know very well how the state sewers work, so we demand that they be investigated in order to clarify the truth. I have also asked the legal services of the Generalitat [government] to study these statements and the relevant legal actions that can be taken. For the truth. For the victims, for the Catalans and for all those who are on the side of peace and democracy.” Catalan Vice President Jordi Puigneró has also demanded an investigation. There is more.