(AP) – The company that produced last night’s fireworks show in San Diego says it’s trying to find out why the tens of thousands of fireworks that had been set up on four barges and a pier all went off at once, instead of being launched over the course of 20 minutes.

August Santore, a part-owner of the company, says a glitch or virus in the computer firing system caused all of the fireworks to go off with one command, minutes before the show had been scheduled to start. He says the precautions that were in place helped keep anyone from being injured.

Santore says the company feels “terrible” about the mishap, which was witnessed by hundreds of thousands of people. The company produced hundreds of holiday shows across the country last night.