Washington (CNN) Prominent California lawmakers were watching closely Tuesday's shooting at YouTube's headquarters, where police say at least one person was dead and three were injured.

The deceased, a female, may have died from a self-inflicted gunshot wound but that is still under investigation, San Bruno Police Chief Ed Barberini told reporters Tuesday afternoon.

Democratic Rep. Jackie Speier, whose district includes YouTube's headquarters, tweeted that the country must take action to end gun violence.

"I am shocked and saddened to hear about another mass shooting, this one at YouTube in my District. I am following developments and am sending prayers to the victims and survivors. We must take action and #EndGunViolence," she tweeted.

I am shocked and saddened to hear about another mass shooting, this one at YouTube in my District. I am following developments and am sending prayers to the victims and survivors. We must take action and #EndGunViolence. — Jackie Speier (@RepSpeier) April 3, 2018

Democratic Sen. Dianne Feinstein also tweeted about the shooting.

Read More