On April 26, 2017, the Spanish police announced that one of the nine men arrested the previous day in connection with the March 2016 terrorist attacks in Brussels was spotted and questioned outside the band's concert venue in Barcelona on September 10, 2016. According to the police source, he was subsequently put under surveillance, as were his entourage, which eventually led to the arrest of the nine men on April 25, 2017, in and around Barcelona.