Sergeant pleads not guilty in guard death

An Air Force staff sergeant pleaded not guilty Thursday to federal charges of murder and attempted murder in connection to the killing of a federal security guard in Oakland.

A federal grand jury indicted Steven Carrillo, a 32yearold Ben Lomond resident, on charges of firstdegree murder of a person assisting an officer or employee of the United States, as well as attempted murder of a person assisting an officer or employee of the U.S.

He is accused of being the gunman who sprayed bullets across a guard shack May 29 in front of the Ronald V. Dellums Federal Building in Oakland, killing 53yearold David Patrick Underwood and wounding another officer. A week after that attack, Carrillo allegedly ambushed sheriff ’s deputies in Santa Cruz County, killing Sgt. Damon Gutzwiller.

On Thursday, Carrillo was appointed a lawyer, James Thomson, who entered the notguilty pleas during a virtual arraignment. Carrillo appeared from Santa Rita Jail via video, wearing jail scrubs and a blue mask that he removed as the hearing started.

His next court date was scheduled for

Aug. 6.

Carrillo, who was active duty at Travis Air Force Base in Fairfield, allegedly plotted the attack in Oakland while protesters marched through the city’s downtown in a demonstration against police brutality, which he allegedly saw as a distraction for authorities.

An accomplice in the Oakland shooting, Robert Alvin Justus Jr. of

Millbrae, is due in court July 23. Federal authorities accused him of being the driver of the van from which Carrillo opened fire on the guard shack.

Justus pleaded not guilty last week to two charges of aiding and abetting Carrillo, according to court records.

The attack set off a weeklong manhunt that ended June 6 in Ben Lomond, where Santa Cruz County sheriff ’s deputies received a call about a suspicious white van abandoned off Jamison Creek Road.

Carrillo allegedly ambushed the responding deputies, killing Gutzwiller and wounding another officer. Prosecutors in Santa Cruz County filed a slew of charges, including murder, in connection to the case.

Federal authorities have linked Carrillo to the Boogaloo movement, an antigovernment extremist group whose supporters believe there is an impending civil war.

Alejandro Serrano is a San Francisco Chronicle staff writer. Email: alejandro.serrano@sfchronicle.com Twitter: @serrano_alej