PROVO, Utah (KTVX) – Several people were injured at a Fourth of July celebration in Provo, Utah, when fireworks reportedly launched into the crowd.

According to initial reports from officials, six people were taken to the hospital with injuries after the incident.

The Stadium of Fire event, an annual Independence Day celebration at Brigham Young University’s LaVell Edwards Stadium, was delayed after the fireworks shot into the crowd during the flag ceremony at the beginning of the event, officials said.

It wasn’t immediately clear what caused the mishap.

Shortly after, viewers also witnessed a small fire in the stands where the fireworks were launched from. The fire was later extinguished.

“Safety is of the upmost importance to us. All pyrotechnics are thoroughly checked before the show, and were rechecked after the incident. Our thoughts are with those who are impacted by the incident and we are following up with them to make sure they are okay,” said Emory Cook, a spokesperson for the event, in a statement.

Viewers who were at the stadium said the show was delayed for about 10 to 15 minutes as medical personnel and other officials responded to the scene. The show resumed just before 9 p.m.