1 Dead, 1 Injured After Explosion at California Elementary School

— -- An 18-year-old man has died after an explosion at an elementary school in California, Ventura County fire officials told ABC News' affiliate KABC.

Officials say a 17-year-old man was also taken to the hospital with minor injuries Monday evening.

It's thought the two men had been making hobby rockets on the basketball courts of Madrona Elementary School in Thousand Oaks, according to fire officials.

The Ventura County Sheriff's Department said an 18-year-old man was taken to the hospital in critical condition and later died from his injuries.

Officials were still investigating the incident.