Joran van der Sloot will serve 28 years in one of the world's toughest prisons

The 24-year-old prime suspect in the murder of Alabama coed Natalee Holloway, sighed and shook his head when he was sentenced by a tribunal in Peru.

"You have been sentenced. Do you have anything to say?"

"I have been told to say nothing," said van der Sloot.

Van der Sloot pled guilty earlier this week to murdering 21-year-old Stefany Flores, who he met at a casino, yet managed to laugh and joke with his attorneys.

There was no laughter Friday. He appeared in the stifling courtroom in a sweat-stained green tee-shirt and denim jeans. He repeatedly wiped his brow with a sleeve and sat fanning himself with his hand.

He is not eligible for release until the year 2038 when he will be a 52-year-old middle-aged man

His sentencing comes just as an Alabama court officially declared Natalee Holloway dead—six years after she disappeared on the island of Aruba.

Holloway's mother, Beth, says she still hopes van der Sloot will one day face justice in a U.S court.

That's if he survives the next three decades in one of South America's most notorious maximum security prisons.