The former Libyan intelligence officer convicted in the 1988 Lockerbie plane bombing was taken to hospital on Saturday for a blood transfusion with his health deteriorating, his family says.
The son of Abdel Baset al-Megrahi, Khaled, said his father was carried to Tripoli Medical Center for the second time in two days.
"My dad's health is very bad and has been worsening," Khaled told The Associated Press at the family house in Tripoli. "He is on his last breath," he added.
Al-Megrahi is the only person convicted for the bombing over Lockerbie, Scotland, that killed 270 people. He was released from a Scottish prison on humanitarian grounds in 2009, eight years into a life sentence. Doctors then predicted that he would die of prostate cancer within three months.
His release infuriated victims' families and their anger grew when he was given a hero's reception in Libya and then lived long past the predictions of the doctors.
Over the past three years, his family has on several occasions said that al-Megrahi is near death, in what was seen as an attempt to justify his release.
"I don't think he can make it this time," his son said Saturday.
Calls for imprisonment
Since his return to Libya, al-Megrahi rarely appeared in public. Libyan dictator Moammar Gadhafi's fall last year spurred calls in the United States and Europe to return him to prison. Two New York senators asked the former rebels to hold al-Megrahi fully accountable for the bombing.
At that time, Libya's rebel leaders, who were scrambling to replace Gadhafi's regime with a government of their own, said they would not deport al-Megrahi or any other Libyan. They then softened their stance, saying that only the future elected government could deal with such issues.
The Lockerbie saga began when a bomb packed into a suitcase exploded inside Pan Am Flight 103 as it flew over Scotland. Among the victims were many American college students flying home for Christmas.
The bombing, which scattered flaming wreckage onto the small town of Lockerbie and killed 11 people on the ground, became one of the most vivid scenes of terrorism of that era, and helped ensure that Libya remained an international pariah state.
Little is known about al-Megrahi. At his trial, he was described as the "airport security" chief for Libyan intelligence, and witnesses reported him negotiating deals to buy equipment for Libya's secret service and military.