The Boston Globe is reporting that nearly 40 concertgoers, many of whom were minors, were taken to local hospitals from the TD Garden last night following an Avicii concert held at the arena. Authorities said many suffered from drug and alcohol problems. There were no fatalities.

Michael Bosse, deputy superintendent for Boston EMS, told the Globe that over 50 people were treated or evaluated at the scene, with another 36 patients transported to hospitals. Police officials deemed the situation a “mass casualty event,” as more than seven ambulances were called to the scene.

Many reports to the Globe suggested that at least three women were carried out by stretchers, with dozens more passing out in what was described as a “hot” and “steamy” arena during the concert.

At Avicii’s Toronto show, 29 people were reportedly hospitalized with various degrees of health problems.