STARKE — Juan Carlos Chavez, who raped and murdered 9-year-old Jimmy Ryce in 1995, said nothing as he went to his execution on a chilly Wednesday night at Florida State Prison.

Chavez's last statement came in a rambling hand-written note penned hours before his death. In it, he made no apologies to the Ryce family.

For Don Ryce, 70, who has spent the past 18 years crusading for tougher laws against sex predators, the execution of his son's killer delivered a message. After stoically watching Chavez, 46, die from a lethal injection, Ryce warned pedophiles to think twice about killing their victims.

"People will not forget, they will not forgive," Ryce said. "We will hunt you down and we will put you to death."

Ryce's older son, Ted Ryce, said he was reluctant to attend but came as "symbol of strength." Jimmy's mother and sister both died in the past few years.

"To show you that in spite of all the terrible tragedies we've been through, my father and I still stand strong — and strength is something we are sorely lacking in our country today," Ted Ryce said.

Jimmy disappeared from a school bus stop Sept. 11, 1995, sparking a massive three-month search across South Florida. Chavez, after a marathon police interrogation, confessed to raping him and shooting the boy in the back as he tried to escape. The ghastly details of the crime — Jimmy's dismembered remains were found in planters sealed with concrete — shook the community's sense of security and spurred legislation allowing the state to indefinitely detain sexual predators.

The execution Wednesday came after a tense delay of two hours as the U.S. Supreme Court considered, but ultimately denied, a last-minute request for a stay.

In the death chamber at 8:02 p.m., a curtain rose that allowed witnesses seated in a brightly lit white room to look through a one-way window at Chavez lying on a gurney.

A prison official supervising the execution asked Chavez if he wanted to make a last statement. Chavez declined and the first of three drugs was administered.

Within a few minutes, a sedative took effect. Chavez yawned and closed his eyes. At one point, the corrections official said his name, "Mr. Chavez," three times to make sure he was asleep. The official then leaned over Chavez and shut his eyelids.

As the lethal components in the injection took effect, Chavez moved his feet slightly. His body lay still for several minutes. A doctor examined Chavez's eyes, nose and mouth. A stethoscope detected no heartbeat. At 8:17 p.m., the corrections official declared Chavez's death.

Throughout the process, none of the 19 witnesses showed any emotion. As he walked from the room with the aid of a cane, however, there was clear pain in Don Ryce's eyes.

Other witnesses included Miami-Dade Assistant State Attorney Penny Brill and former prosecutor Michael Band, both of whom took Chavez to trial. Former Miami-Dade homicide sergeant Felix Jimenez attended, as did one juror who helped convict Chavez in 1998.

Pat Diaz, the retired Miami-Dade police detective who led the investigation into Jimmy's murder but did not attend the execution, still felt a sense of closure.

"Justice has been served for an evil man," he said.

Earlier in the day, Chavez's only visitor was a "spiritual adviser." His demeanor during the day was calm, a Florida corrections spokeswoman told reporters. His last meal included a ribeye steak, French fries, a fruit cup and strawberry ice cream and mango juice.

The notoriety of the case drew an unusually large media contingent. About two dozen news reporters, photographers and TV satellite trucks gathered under drizzling gray skies in a sprawling field across from the Florida State Prison.

Chavez, who spent nearly 16 years on death row, was the 12th inmate put to death in Florida since the start of 2012.

The day started off with the Florida Supreme Court rejecting a last-minute bid to delay the scheduled execution.

Chavez's lawyer, Robert Norgard, tried to persuade the Florida Supreme Court to reconsider Chavez's argument that the sedative used as part of the cocktail of lethal drugs was ineffective as a pain-relieving anesthetic and therefore violated his constitutional protection against "cruel and unusual punishment."

But the Florida Supreme Court concluded that Chavez should have presented this evidence when he had the opportunity before the justices rejected his previous bid for a stay Jan. 31.

For Chavez, a farmhand who confessed to the crime, the final word came early in the evening in the form of a terse denial from the nation's highest court.

The disappearance of Jimmy, a bright boy with a passion for baseball and chess, shook South Florida.

It echoed a notorious child-kidnapping 14 years earlier, when 6-year-old Adam Walsh was abducted from a Hollywood shopping center. Adam's severed head was the only part of his body ever found.

Jimmy vanished after he exited a school bus a few blocks from his home in the Redland, a rural area with farms, ranches, and large residential properties. His parents, both lawyers, were out of town on business.

It wasn't until three months later that Chavez's landlady discovered the boy's book bag and the murder weapon in his trailer.

Diaz, the lead homicide investigator in the case, said the boy's murder was among the most heinous in his 33-year career.

"Making this case was life and death," Diaz said. "There was no room for failure."