"I want the U.S. government to look into who else was involved in this," she said Cohen.
Al-Megrahi, a Libyan intelligence officer, was jailed for the bombing in 2001, but insisted that he had nothing to do with it. He was allowed to return home in 2009 after doctors said he would die of prostate cancer within three months.
Cohen thinks he should have gotten the death penalty, not a comfortable death in Libya with his family. "My daughter died a gruesome, horrible death at the age of 20," she said.
Cohen said she felt "joy" when Moammar Gadhafi died in 2011 "because he was the real killer." What she felt for al-Megrahi was more muted but, at 74, she was glad to have outlived him. She said she "would like to have killed him on the spot" at his trial.
She scoffed at the idea of closure. She is still angry and said she always will be. Her life went on after the death of her only child, but she has not recovered. "It destroys you," she said. "It destroyed me 23 years ago. . . . It takes the heart out of you and there is no escape from that."
Maslowski, whose 30-year-old daughter, a bond trader, died on the plane, said he heard about al-Megrahi's death just before 8 a.m. It brought back all the old emotions.
"We'll remember it 'til the day we die," he said.
He wonders if all the guilty parties will ever be caught. He said al-Megrahi's death might bring closure, but sounded unconvinced.
New Jersey's two U.S. senators, both Democrats who had strongly opposed al-Megrahi's release, vowed that investigations into the bombing would continue.
"I know that justice has not been fully served and I intend to continue to fight to ensure all leads are pursued, so that we find the truth," Sen. Bob Menendez said in a statement. "I will judge the Libyan government by their commitment to assist us with access to the files and people left from the ousted (Moammar Gadhafi) regime, so that justice can be finally served."
Sen. Frank Lautenberg, who served on a presidential commission that investigated the bombing and played a role in securing compensation for the victims' families, said al-Megrahi "died with American blood on his hands and will always be remembered as a murderer."
Contact staff writer Stacey Burling at 215-854-4944 or firstname.lastname@example.org.
The Associated Press contributed to this article.