He shot himself when police surrounded a white pickup truck in Torrance, about 30 miles from Monterey Park, Los Angeles County Sheriff Robert Moon said.
The incident took place at around 10:22 pm. Between 17 and 20 minutes, a gunman had appeared at another dance studio in the nearby Alhambra.
A group of people confiscated a gun from him.
On Sunday morning, agents in Torrance spotted a white pickup truck matching the description.
When the officers got out of their patrol car, they heard shots fired from a truck and found Tran dead inside.
The motive for the shooting is not yet known and a search warrant has been issued for Tran's home to look for leads.