The City of Los Angeles (LA) transportation network includes more than 1300 state and local bridges, which are vulnerable to the earthquake shaking. Seismic damage to these bridges will incur significant repair costs and hinder post-earthquake emergency response and long-term recovery of LA communities. This study conducts a stochastic event-based regional seismic damage assessment of LA's bridge network. The bridges that comprise the network vary based on the construction era, geometry, connectivity, material properties, and design detailing. To capture these variations, Google Street View and the US National Bridge Inventory (NBI) database are used to classify the LA bridges into 26 groups based on their abutment type, construction era and the number of spans and columns. Subsequently, a new generation of component-level seismic fragility models is synthesized from the literature and assigned to each bridge group. The fragilities capture damage to columns, bearings, shear keys, joint seals, deck (unseating), and foundation. The new-generation seismic fragilities, which represent a significant advancement relative to existing models for California bridges, were developed using finite element models that explicitly capture component-level demands and limit states across the identified 26 bridge groups. The third Uniform California Earthquake Rupture Forecast (UCERF3) model is used to generate 1000 earthquake catalogs in 50 years. Each catalog produces approximately 400 earthquake events throughout California. Region-consistent ground motion prediction equations and spatial correlation models are applied to simulate 100 ground motion random fields (GMRF) under each event. The GMRFs are then convolved with the fragility models to estimate the distribution of shaking intensities at each bridge location and the associated component-level damage state exceedance probabilities. Damage assessment results from the current study facilitate the development of seismic risk and resilience models of the LA bridge network. The ultimate goal is to inform risk- and resilience-based seismic retrofit programs, as well as post-earthquake decision-making and restoration planning for the City of LA.