An Indiana man whose cross-country crime spree with his girlfriend a decade ago ended in a gun battle with police in San Francisco was executed Thursday in Texas for killing a sheriff's officer.

Joshua Maxwell's voice broke as he apologized repeatedly in the seconds before the state put him to death by lethal injection for the October 2000 slaying of Bexar County sheriff's Sgt. Rudy Lopes.

"The person that did that 10 years ago isn't the same person you see today," Maxwell said. "I hurt a lot of people with decisions I made. I can't be more sorry than I am right now."

He said his execution was "creating more victims."

"This is not gonna change anything," he said.

Maxwell, 31, was the fourth inmate executed this year in the nation's busiest capital punishment state. No late court appeals were filed for him. The U.S. Supreme Court last week refused to review his case.

Lopes, a 45-year-old veteran jailer, was robbed of his truck and shot. His bound and blindfolded body was found behind a San Antonio shopping mall.

Maxwell and his girlfriend, Tessie McFarland, crisscrossed the country in a deadly crime spree, starting in Indiana with the robbery and slaying of Robby Bott, 45, a FedEx mechanic from Mooresville, Ind., a month before Lopes' slaying.

Bott's parents joined three relatives of Lopes on Thursday as witnesses in the Texas death chamber. Maxwell's son, mother and half-sister watched through a window in an adjacent room.

After Maxwell was pronounced dead, Shirley Bott turned to a state official accompanying her and showed a heart-shaped locket she wore on a chain around her neck.

"I have my son's ashes in here," she said. "I wanted him to be here."

Maxwell and McFarland were arrested less than a week after Lopes' body was found. They had a chase and running gun battle with police through downtown San Francisco after Maxwell, driving Lopes' stolen truck, refused to be pulled over for running a red light.

Maxwell was convicted of capital murder and sentenced to death in Lopes' killing. In Indiana, he was convicted of murder, felony confinement, arson and theft in Bott's slaying.

McFarland, 30, is serving a life prison term in Texas after pleading guilty to Lopes' slaying. In Indiana, she initially was charged with murder, criminal confinement, arson and theft in Bott's killing, but pleaded guilty to confinement and arson as part of a plea deal.