Ousted Iraqi leader Saddam Hussein was hanged on Saturday, state run Iraqiya television reported.
"The execution of Saddam Hussein is complete," the channel said in a text headline broadcast against a background of Koranic verses.
Saddam and his two co-accused — his half brother and intelligence chief Barzan Hassan al-Tikriti and revolutionary court judge Awad Ahmed al-Bandar — were convicted of crimes against humanity by an Iraqi court on November 5.
Over the previous months, the Iraqi High Tribunal in Baghdad heard how they oversaw a campaign of collective punishment against the Shiite village of Dujail, north of Baghdad, where Saddam escaped an assassination bid in 1982.
Dujail's orchards were torn up and 148 men and boys were executed after being dragged through Bandar's kangaroo court.
More than 20 years later, Saddam was overthrown by a US-led invasion and later put on trial by a new Shiite-led government. The trio's death sentences were confirmed by a panel of appeal court judges on December 26.
The hangings then became inevitable, with Prime Minister Nuri al-Maliki's government determined to avenge Saddam's brutal 24-year reign and to strike a blow against a violent Sunni insurgency that still honours his name.
Saddam's Jordan-based defence team, which largely boycotted the year-long trial, made one last desperate shake of the dice by going to court in the United States to demand that the ousted despot remain in US military custody.
But US authorities in Baghdad insisted that the detainees have been under Iraqi legal authority for more than a year and were only being held in an American military base as simple a security precaution.
Saddam's trial was the subject of fierce criticism from Sunni Iraqis — who accused the court of being a puppet of Iraq's US occupiers and the Maliki government's Iranian allies — and from international rights groups.
Human Rights Watch and Amnesty International both complained that Maliki's government had pressured the judge to return guilty verdicts, and called for the accused to be brought before an international tribunal.
"Imposing the death penalty, indefensible in any case, is especially wrong after such unfair proceedings," said Richard Dicker, director of Human Rights Watch's international justice programme, after the appeal failed.
But the hanging is likely to be broadly welcomed among Iraq's majority Shiite population, which held noisy street parties to celebrate Saddam's arrest in December 2003 and conviction this year.
Security officials also fear a backlash, however, from hardline factions among Iraq's Sunni minority, including the Islamist and nationalist militant groups that make up the deadliest elements of Iraq's violent insurgency.
Ahead of the verdict, the head of Iraq's interior ministry command centre, Brigadier General Abdel Karim Khalaf, said that the country's beleaguered security forces were on high alert.
"Certainly, this is a big event, putting into effect the execution of this serial killer," he said. "We will take measures proportionate to this event. We will put all our forces on the streets so that no lives are jeopardised."
After Saddam's conviction in November, authorities imposed a three-day curfew across much of the country, shutting down all life in Baghdad and sealing Iraq's borders and airports in a bid to head off reprisals.
State television, the Iraqiya network, prepared the ground for Saddam's execution by showing gruesome footage of his soldiers mutilating and beating prisoners, throwing a detainee from a roof and filling mass graves.
National Security Adviser Mowaffaq al-Rubaie told broadcasters that the hanging would be videotaped, and that footage might be released later, but officials said no journalists would be allowed to watch the hanging.