WASHINGTON, Dec 23 (Reuters) - Alphabet GOOGL.O unit Waymo said on Tuesday it will expand first responder engagement, improve its emergency response protocols and roll out updates to allow its vehicles to navigate intersections more decisively, following incidents of stalled Waymo robotaxis after a San Francisco power outage.

Waymo paused service Saturday evening following a fire at a PG&E substation that knocked out power to roughly one-third of the city, affecting about 130,000 residents and forcing some businesses to close temporarily.

A California regulator said on Monday it was looking into incidents in which Waymo's robotaxis stalled in parts of San Francisco because of the outage.

(Reporting by Kanishka Singh in Washington; Editing by Christian Schmollinger)

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