SANTA ROSA (CBS SF) — Two teens pleaded not guilty in Sonoma County Superior Court Monday morning to killing a man at a party in Santa Rosa on New Year’s Eve.

Joseph Mario Varela, 15, of Santa Rosa, and Manuel Syphanh Khiobouakham, 19, of Rohnert Park, are charged with the fatal shooting of Damien Wadell Toney Jr., 20, of Santa Rosa, at an apartment complex at 2001 Piner Road around 2 a.m. on Dec. 31.

READ MORE: Power Plant at Oroville Dam Reservoir Shut Down for First Time Due to Lack of Water

Varela is being tried as an adult.

Santa Rosa police said both of the teens were armed and shot Toney during a dispute that started inside the party and continued outside.

Toney was found on the ground in a parking lot at the apartment complex in northwest Santa Rosa. He suffered bullet wounds to the torso and arm and was taken to Santa Rosa Memorial Hospital but did not survive, police Sgt. David Linscomb said.

Varela was found in the residence of an acquaintance and police recovered a weapon used in the shooting, Linscomb said.

Forensic evidence indicated two guns were used in the slaying and police got a search warrant for Khiobouakham’s arrest. He was arrested on Feb. 3 on suspicion of murder when he went to the Sonoma County courthouse on an unrelated warrant.

Many witnesses to the shooting were uncooperative, Linscomb said.

READ MORE: Dixie Fire Update: Buildings Burn In Canyondam; Fire Advance Forces Lassen Volcanic National Park Shut Down

Khiobouakham’s attorney Joseph Stogner said Toney was acting extremely violently that night and there is insufficient evidence that Khiobouakham was involved in the shooting.

“Witnesses said the alleged victim attacked at least one woman at the party. There will be sufficient evidence to support self-defense,” Stogner said after today’s brief hearing.

“I have not seen any evidence of two firearms,” Stogner said.

The two defendants were on friendly terms at the time of the murder, Stogner said.

Prosecutors have not disclosed a possible motive for the killing nor the relationship between the defendants and the victim.

A preliminary hearing in the case is scheduled for May 12.

MORE NEWS: Reports of Breakthrough COVID-19 Infections Cause Concern

Copyright 2014 by CBS San Francisco and Bay City News Service. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.