(CBS SF/CNN) -- Two additional pipe bomb packages have been discovered addressed to California Sen. Kamala Harris and the Bay Area home of billionaire activist Tom Steyer, the latest high-profile critics of President Donald Trump targeted in a wave of suspected pipe bomb mailings.
Law enforcement sources told KPIX 5 the package addressed to Steyer was intercepted by authorities at a Burlingame mail distribution center near San Francisco International Airport. Employees were moved into the parking lot as the operation unfolded.
Helicopter video of the facility showed federal, local and state agents swarming around the building and an officer dressed in a bomb protection suit entering a door.
Burlingame police later tweeted that the package was similar to the other packages mailed across the country and threat had been contained. "The package is consistent with the mailings throughout the nation," the tweet said. "The package has been removed from that facility and the area has been rendered safe."
Some two dozen employees were evacuated from the building during the operation. A postal service spokesman credited an national security protocol briefing for helping employees know what to look for. "They were given visuals of what to look for, the dimensions, whatever was out of the ordinary," said spokesman Augustine Ruiz.
The FBI Sacramento Field Office said the device addressed to Sen. Harris was discovered at a Sacramento mail facility, and it was rendered safe by bomb technicians. The office encouraged the public be aware of their surroundings and report any suspicious packages to 911.
Sen. Harris' office said authorities confirmed the suspicious package addressed to her was similar to the packages those sent to other elected officials.
Harris spokeswoman Lily Adams said in a statement, "At this moment, it is incumbent upon leaders across the political spectrum to take seriously the power they hold. It is the responsibility of our leaders to use their role as public figures to elevate our discourse and bring people together."
Suspicious packages addressed to Sen. Cory Booker (D-New Jersey), former Director of National Intelligence James Clapper were also reported on Friday.
Earlier Friday, authorities arrested Florida resident, Cesar Sayoc, in connection with the series of mail bomb threats to top Democratic party leaders and critics of President Trump, including former President Barack Obama, former Secretary of State Hillary Clinton and former Vice President Joe Biden.
Images of the Sayoc's van seized by federal agents showed the windows covered with a variety of stickers and placards in support of President Trump.
FBI Director Christopher Wray said Friday that 13 improvised explosive devices were sent across the county. "These are not hoax devices," said Wray.
Steyer, a San Francisco resident and hedge fund manager, liberal activist and philanthropist, is leading an petition effort calling for President Trump's impeachment.
Speaking at the White House Friday afternoon, Trump congratulated law enforcement on the arrest and denounced what he called "terrorizing acts." He also called for unity: "peace and love and harmony as fellow Americans."
His remarks came after he has blamed the media this week for rising "anger" in the country while refusing to acknowledge his own role in contributing to divisive rhetoric in the public discourse.
"We must never allow political violence to take root in America," Trump said at one point. "I'm committed to doing everything in my power as President to stop it."
As the situation initially unfolded mid-morning -- before the arrest was announced -- the President complained on Twitter that the news media was busy reporting on "'Bomb' stuff" and not politics.
"Republicans are doing so well in early voting, and at the polls, and now this 'Bomb' stuff happens and the momentum greatly slows - news not talking politics. Very unfortunate, what is going on. Republicans, go out and vote!" Trump tweeted.
© Copyright 2018 CBS Broadcasting Inc. All Rights Reserved. CNN contributed to this report.
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