Federal authorities on Wednesday announced the indictment of eight members and associates of a Santa Rosa gang on a variety of charges including racketeering, attempted murder, robbery and drug trafficking.

The U.S. Attorney's Office in San Francisco released details of the alleged gang conspiracy contained in a 17-count federal grand jury indictment against the Varrio South Park gang.

Three defendants were arrested Tuesday night in a joint law enforcement operation in Sonoma County.

Four additional defendants were already in custody at the Sonoma County Jail and were transferred into federal custody to face charges.

All were arraigned in federal court Wednesday, except for one defendant who is being sought, according to the statement from U.S. Attorney Melinda Haag.

The 34-page indictment detailed a long list of charges, including assaults and shootings.

It describes the Varrio South Park gang as first appearing in Santa Rosa in the early 1990s, when several members of an existing norte? gang in Santa Rosa — the South Side Posse — split because of internal disagreements over the gang's racial composition.

According to the indictment, there are approximately 90 active VSP members.

The suspected racketeering conspiracy has occurred since at least the mid-2000s, according to the indictment.

Santa Rosa Police Chief Tom Schwedhelm said Wednesday night that it's "a big deal" that federal authorities became involved.

"It infers it's not just a Santa Rosa situation," he said of the scope of the criminal activity.

"The federal government does not have unlimited resources. To get the attention of the U.S. Attorney, it has to be a fairly significant case," he said.

He noted that there is a Safe Streets Task Force that focuses on gangs and includes Santa Rosa Police, the FBI, CHP and the Sonoma County District Attorney's Office.

Those agencies were given credit by the U.S. Attorney's Office for collaborating in the grand jury case, along with the Sonoma County Sheriff's Department and state Department of Corrections.

Despite the indictments announced Wednesday, Schwedhelm said gang activity in Santa Rosa is down 2 percent through the first three quarters of this year, compared to the same period in 2012. "Things are trending in a positive direction," he said.

The police chief said that off-hand, he could not recall a similar federal indictment involving Santa Rosa gang members, other than the "Operation Black Widow" case in 2001, which resulted in federal indictments of 21 reputed gang members on murder, racketeering and weapons charges.

That three-year investigation, which began with a tip to Santa Rosa Police, infiltrated the hierarchy of gangs run by prisoners at Pelican Bay State Prison in Crescent City who allegedly ordered murders and other violent crimes from behind bars.

Of the eight defendants named in this week's indictment against the Varrio South Park gang, seven — David Martinez, Edmund Deneiliom, Ruben Quiroz, Cesar Castellanos, Lucio Mendoza, Samuel Tewolde and Kalin Carell — are charged with racketeering conspiracy, conspiracy to commit murder in aid of racketeering and conspiracy to commit assault with a dangerous weapon in aid of racketeering, arising from participation in the gang.

Martinez, also known as "Fat Boy," "Oso" and "Big Homie," is described as the gang's "regimental commander." He and Quiroz are also charged with conspiracy to commit a robbery affecting interstate commerce and a robbery affecting interstate commerce arising from an Aug. 19 robbery and car chase during which Martinez is suspected of firing shots at the victim's vehicle.

According to news reports at the time, the incident stemmed from a late-night marijuana deal in a west side Santa Rosa commercial center when some of the gang members pulled out guns and robbed the other side.

Tewolde and Castellanos, who is also known as "Cheese," are each charged with separate counts of attempted murder in aid of racketeering.

The attempted murder charge against Tewolde arises from an incident on Sept. 5 in the parking lot of Chevy's restaurant in Railroad Square, where he is suspected of firing shots at an individual whom he believed to have "snitched" against other members of VSP, according to authorities.

No one was injured by the gunfire, though one nearby vehicle was struck, according to police.

Castellanos' attempted murder charge arises from an incident on Oct. 9, where he is suspected of shooting and wounding a fellow gang member whom he believed to have challenged his status and authority within the gang.

Castellanos also is charged with one count of witness tampering. He is suspected of threatening to kill a woman to prevent her ex-boyfriend from testifying against Tewolde.

Martinez and Deneiliom, also known as "EZ," are charged with trafficking methamphetamine and marijuana. Deneiliom and Andrew Hill-Piccola are also charged with being felons in possession of firearms.

You can reach Staff Writer Clark Mason at 521-5214 or clark.mason@pressdemocrat.com.