WASHINGTON (AP) — Democratic presidential front-runner Joe Biden has formally requested protection from the U.S. Secret Service, according to two people familiar with the matter.

Biden's request begins a process by which the Department of Homeland Security will decide whether to provide the campaign with protection, though that was expected to be concluded swiftly with a favorable outcome, the two people said. The two spoke to The Associated Press on Thursday on condition of anonymity to discuss the sensitive matter.

Congressional leadership was notified of the Biden campaign's request, and the DHS secretary will make the final determination. Biden campaign spokesman TJ Ducklo said, “We don't comment on security measures."

The move comes a week and a half after two protesters rushed a stage in Los Angeles and came within feet of Biden during a Super Tuesday victory speech. Biden's wife, Jill, and several staff members, including one trained security officer employed by the campaign, physically restrained the women and carried them from the stage. Neither the former vice president nor his wife was hurt.

The leading candidates in the 2012 and 2016 presidential contests had Secret Service protection by this point in those races. Neither Biden nor Vermont Sen. Bernie Sanders had requested protection until now.

The Secret Service protects, by statute, the president and vice president and their families, as well as some other senior government officials. It is also authorized to provide protection to major party presidential candidates, an authority granted after the assassination of Robert F. Kennedy in 1968.

The agency said in a statement last week that it has been preparing for the 2020 campaign since January 2017, with specific training underway since early 2019. The agency said thousands of agents, officers and support staff have been identified to assist in the campaign and went through training last year that included "instruction related to physical protection, threat assessments, emergency medicine, and constitutional law."

Biden, code-named “Celtic,” had Secret Service protection from the time he was selected as Barack Obama's running mate through about six months after his term as vice president expired in 2017. Unlike presidents, the protection of former vice presidents does not last for life.

The process for assigning a security detail to a candidate generally requires that campaigns initiate the request for protection. The Secret Service does a threat assessment and consults with DHS officials and a congressional commission made up of the majority and minority leaders of both chambers, plus another member. The ultimate decision on whether to provide protection is made by DHS.

Some campaigns can be resistant to requesting protective details because of the additional logistical and planning constraints put on by the Secret Service's security requirements.

Last week, Rep. Cedric Richmond, D-La., said the House Homeland Security Committee has asked the Secret Service to provide protection to all remaining major presidential candidates.

Richmond, one of Biden’s campaign co-chairmen, said members of Congress were “very worried” about the March 3 episode, when the protesters rushed the stage at a Biden speech in California.

He isn't the only candidate to have been accosted at a campaign event. Topless demonstrators crashed a Sanders rally in Nevada in February.

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