[What follows is a brief excerpt from the Wikipedia article on Abdelbaset al-Megrahi:]
In November 1991, Megrahi and Fhimah were indicted by the US Attorney General and the Scottish Lord Advocate for the bombing of Pan Am Flight 103. Libya refused to extradite the two accused, but held them under armed house arrest in Tripoli, offering to detain them for trial in Libya, as long as all the incriminating evidence was provided. The offer was unacceptable to the US and UK, and there was an impasse for the next three years.
On 23 March 1995, over six years after the 1988 attack, Megrahi and Fhimah were designated as United States fugitives from justice and became the 441st and 442nd additions on the FBI Ten Most Wanted Fugitives list. This list offered a US $4 million reward from the US Air Line Pilots Association, Air Transport Association, and United States Department of State, and $50,000 from the Federal Bureau of Investigation (FBI), for information leading to their arrest.
The parties eventually agreed on a compromise and a trial was held in the Netherlands under Scots law. The trial format was engineered by legal academic Professor Robert Black of the University of Edinburgh and was given political impetus by the then British foreign secretary, Robin Cook.
Protracted negotiations with the Libyan leader, Colonel Muammar Gaddafi, and the imposition of UN economic sanctions against Libya brought the two accused to trial in a neutral country. Over ten years after the bombing, Megrahi and Fhimah were placed under arrest at Camp Zeist in the Netherlands on 5 April 1999. During his seven-year house arrest awaiting deportation and trial, Megrahi lived on a Libyan Arab Airlines pension and worked as a teacher.
[RB: A reward of "up to $5 million” is still on offer under the US Rewards for Justice scheme “for information leading to the arrest and/or conviction of those responsible for the bombing of Pan Am Flight 103 and the murders of the 270 victims”.]