The Los Angeles Police Department ended its protection services for former Vice President Kamala Harris on Saturday after facing criticism from an elite unit of its officers and the police union, according to two people familiar with the matter.

The police force stopped providing the services for Ms. Harris on Saturday morning, according to a law enforcement official and a person with close ties to the department. They spoke on the condition of anonymity to discuss closely held security details.

The department said this week that it had assigned officers to assist the California Highway Patrol in providing security for Ms. Harris. The agencies stepped in to fill the security gap that was left after President Trump terminated Ms. Harris’s Secret Service security detail beginning Monday.

The U.S. Secret Service usually protects vice presidents for six months after they leave office, but President Joseph R. Biden Jr. had signed an executive order to extend that protection for an additional year for Ms. Harris.

The decision to dispatch the Los Angeles police to guard the former vice president was met with swift criticism from officers within one of the department’s specialized units, known as the Metropolitan Division, the people familiar with the matter said. Officers had been reassigned from crime suppression work in the San Fernando Valley, one of those people said. The request for the protection service came as the department was already trying to manage with reduced resources, the law enforcement official said.

The Los Angeles Police Protective League, the union that represents L.A.P.D. officers, had criticized the use of police officers to protect Ms. Harris, calling the operation “nuts” and a misuse of taxpayer money.