The grisly murder and robbery of an elderly couple in Waterloo, Iowa, stunned the community three decades ago. But the case remained unsolved until a 66-year-old man walked into a police station and confessed on Wednesday.

Jack Wendell Pursel was in court today for an initial appearance, where a judge raised Pursel's bail from $500,000 to $2 million for shooting Richard Huntbach, 85, and wife Goldie, 77.

On Wednesday, Pursel, who most recently lived in South Gate, Calif., told Waterloo police details about the crime only someone involved with it would know, said Capt. Tim Pillack of the Waterloo Police Department. The town, located along the Cedar River, is home to nearly 70,000 residents, according to the 2010 U.S. Census.

"He just wanted to get it off his mind," Pillack told ABCNews.com. "He knew of the family. He said his intention was to go in and rob them and kill them."

After the Huntbachs didn't answer their door on Jan. 12, 1981, a friend alerted officers.

The "nice elderly couple" was found tied up, gagged and shot to death. Their home had been ransacked.

At the time of the murder, Pillack said authorities interviewed "a lot of people," including Pursel, but weren't able to make any arrests. He may have dated a relative of the couple around the time of the crime, the Associated Press reported.

Soon after, Pursel moved to California, where he was convicted of two counts of oral copulation with a minor, according to California's sex offender registry.

Months after the Waterloo killings, Pursel began serving a 21-year sentence for the two sex offenses; however, he was paroled in 1992. He was completely discharged from his sentence in September of 1995, the Waterloo-Cedar Falls Courier reported.

The convicted felon wanted to make amends with his past, Dan Trelka, director of Waterloo's safety services, told the newspaper.

"It's my understanding he found Christ and felt this was the right thing to do," he said.

After three decades, Pillack said he's happy the Waterloo Police Department can put the cold case to rest.

"We were able to put someone in jail and close the case. It's a great day," he said.

Pursel is being held in the Black Hawk County Jail and is charged with two counts of first degree murder. His preliminary hearing is scheduled for May 18.