UnitedHealthcare CEO murder suspect's mom filed missing person's report in SF, sources say

NEW YORK -- Sources tell ABC News that the mother of the suspect in the killing of UnitedHealthcare CEO Brian Thompson had filed a missing person's report for her son in San Francisco in November.

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Luigi Nicholas Mangione was arrested Monday in the Dec. 4 attack on Thompson after police say a worker at a McDonald's in Altoona, Pennsylvania, alerted them to a customer who resembled the suspected gunman. When arrested, Mangione had on him a gun that investigators believe was used in the attack and writings expressing anger at corporate America, police said.

When asked about the report, SFPD referred ABC News to the NYPD.

This was not the only connection Mangione had with the Bay Area. ABC7 News I-Team reporter Dan Noyes uncovered that Mangione worked as a head counselor at Stanford in 2019 after attending an elite high school in Baltimore and earning his bachelor's and master's degrees in Pennsylvania.

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After his time at Stanford, Mangione headed off to a job in computer programming.

Mangione, who was arrested in Pennsylvania on Monday and faces charges in New York including second-degree murder, is challenging his extradition. His defense was given 14 days to file a formal challenge.

The Associated Press contributed to this report.