Update 10:35 a.m. Authorities state that: "(T)he suspect from last night's incident in the Presidio is Eric Smith, 46 year old male resident of San Francisco."
According to a Golden Gate National Recreation Area statement:
During a vehicle stop being conducted by a US Park Police officer last night just after 9:00PM, the driver of the vehicle volunteered that he had what he termed as fireworks in the vehicle. Upon initial visual investigation the US Park Police officer deemed it necessary to call for the SFPD Bomb Squad to assess the true nature of the items the suspect handed over. The incident occurred near 900 Mason Street, in the San Francisco Presidio, near Crissy Field.
As a safety precaution two businesses in the area, House of Air and Planet Granite, were evacuated and the road was closed. The bomb technician was unable to visually determine the identity of the explosive device, but confirmed that they were active with the potential to be detonated. The SFPD Bomb Squad removed the explosives to a safe location, away from people and the wildlife protection area, and detonated them at 1:15AM.
US Park Police are investigating with cooperation from the SFPD. The suspect was arrested for possession of illegal substances. Other charges are pending results of the investigation.
The arrest occurred along a route that approaches the base of the Golden Gate Bridge. A spokeswoman for the park service, Alexandra Picavet, stated in an email to KQED that authorities don't know where the driver was headed: "Speculation as to his intent and destination. Investigation is still underway."