Tom GeogheganBBC News and Bernd Debusmann JrBBC News, The White House
President Donald Trump has cancelled Secret Service protection which had been arranged for Kamala Harris by Joe Biden before he left office, according to one of her advisers.
As a former vice-president, Ms Harris was entitled under law to receive six months of this extra security after leaving office in January.
Her protection had been extended for another year by an executive directive signed by her former boss but this was revoked by Trump in a memo, seen by the BBC, which is dated Thursday.
The BBC has asked the White House and the Secret Service for comment.
The move comes just weeks before Harris embarks on a national book tour to promote "107 Days" - a memoir of her short-lived and ultimately unsuccessful presidential campaign in 2024.
A copy of a letter seen by the BBC, dated 28 August, directs the Secret Service to "discontinue any security-related procedures previously authorised by Executive Memorandum, beyond those required by law" for Harris from 1 September.
The loss of Harris' secret security protection means she will lose the agents that are assigned to protect her and her property in Los Angeles, as well as proactive threat intelligence carried out to identify and pre-empt any potential threats.
The price of similarly protections, if privately funded, could add up to millions of dollars per year.
It is unclear who will provide the former vice president's protection in the future, but California Governor Gavin Newsom and Los Angeles Mayor Karen Bass have both expressed outrage at the announcement.
Since returning to the White House in January, Trump has revoked Secret Service protections for a number of people, including Hunter and Ashley Biden, the children of the former president, and Anthony Fauci, the former director of the National Institute of Allergy and Infectious Diseases.
Several former Trump officials and allies have also had their protections revoked, including ex-Secretary of State Mike Pompeo and John Bolton, a former national security advisor who had become a vocal critic.