Stanley Tookie Williams, whose self-described evolution from gang thug to antiviolence crusader won him an international following and nominations for a Nobel Peace Prize, was executed by lethal injection early today, hours after Gov. Arnold Schwarzenegger refused to spare his life.

His death was announced at 12:35 a.m.

During the execution, the inmate’s friend Barbara Becnel and other supporters mouthed "God bless you" and "We love you" and blew kisses to Williams. Williams also seemed to mouth statements to Becnel.

The entire procedure took longer than usual. The execution team took about 12 minutes to find a vein in Williams’ muscular left arm. While the personnel were probing, Williams repeatedly lifted his head off the gurney, winced visibly, and at one point appeared to say: "Still can’t find it?"

After Williams was pronounced dead, Becnel and two other supporters of Williams turned toward the media in the witness room and yelled in unison, "The state of California just killed an innocent man!"

Lora Owens, murder victim Albert Owens’ stepmother, appeared shaken, and was embraced by another woman.

Outside the gates of San Quentin as midnight approached, speakers urged calm. There was a moment of tension when a Williams’ friend, Fred Jackson, told the crowd, "It’s all over."

Angry shouts broke out. A woman sobbed on someone’s shoulder, and a man burned an American flag. As Jackson continued to urge calm, the crowd dispersed.

Speaking outside the gates of San Quentin after the execution, Becnel, who is taking possession of Williams’ body, called Schwarzenegger a "cold-blooded murderer" and vowed to work for his defeat in the next election.

Despite persistent pleas for mercy from around the globe, the governor earlier in the day had said Williams was unworthy of clemency because he had not admitted his brutal shotgun murders of four people during two robberies 26 years ago.

After the U.S. Supreme Court denied a request for a last-minute stay Monday evening, the co-founder of the infamous Crips street gang — who insisted he was innocent of the murders — became the 12th man executed by the state of California since voters reinstated capital punishment in 1978.

With its racial overtones and compelling theme — society’s dueling goals of redemption and retribution — the case provoked more controversy than any California execution in a generation, and became a magnet for attention and media worldwide.

A long list of prominent supporters — as disparate as South African Bishop Desmond Tutu and rapper Snoop Dogg — rallied to Williams’ cause.

But in a strongly worded rejection of Williams’ request for clemency, Schwarzenegger said he saw no need to rehash or second-guess the many court decisions already rendered in the case, and he questioned the death row inmate’s claims of atonement.

Williams, the governor said in a statement, never admitted guilt, plotted to kill law enforcement officers after his capture, and made little mention in his writings of the scourge of gang killings, which the statement called "a tragedy of our modern culture."

As night descended Monday, about 1,000 demonstrators who gathered on a tree-lined street leading to the gates of San Quentin State Prison endured frosty temperatures to protest the execution.

Joan Baez sang "Swing Low, Sweet Chariot" as speakers urged participants to keep fighting. Small clumps of people in scarves and gloves held candles and sang hymns, while others wandered off alone, gazing into the bay.

There were small, scattered protests around the state, including a candlelight vigil Monday night in Leimert Park.

A few death penalty supporters also turned out at San Quentin. Scuffles and shoving matches broke out on occasion, but no serious incidents were reported.