Mauritania extradited Moammar Gadhafi’s former spy chief back to Libya on Wednesday, prompting calls from an international human rights group that he be tried before the International Criminal Court.
The handover of Abdullah al-Senussi was a victory for Libya’s fledgling government, which has since March sought to take custody of Gadhafi’s brother-in-law and dreaded intelligence chief.
It was, however, likely to heighten tensions between Libya and the International Criminal Court, based in The Hague.
The court wants custody of Mr. al-Senussi and Gadhafi’s son, Seif al-Islam. It has charged both with crimes against humanity at the start of the revolution in February 2011.
Photographs and videos posted on social media showed a bearded and smiling Mr. al-Senussi, recognizable by his thick, curly black hair, being escorted off a helicopter.
Libyan officials later confirmed his arrival in the country.
Western and Libyan officials have linked Mr. al-Senussi to the 1988 bombing of PanAm Flight 103 over Lockerbie, Scotland, that killed 270 people, mostly Americans.
And Libyan officials have accused him of other crimes, including the massacre of more than 1,200 detainees at Tripoli’s notorious Abu Salim prison in 1996. It was not clear what charges the Libyan government would bring against Mr. al-Senussi.
Libya is obligated by a U.N. Security Council resolution to cooperate with the International Criminal Court, and Amnesty International said Libya must immediately hand over Mr. al-Senussi to the court.
“The ICC arrest warrant for al-Senussi remains in force, and Libya has an obligation to surrender him without delay to The Hague,” said Marek Marczynski, international justice research, policy and campaign manager at Amnesty International.
France also wants custody of Mr. al-Senussi, whom it charged in absentia for his role in a 1989 airline bombing that killed 54 French nationals.
Mr. al-Senussi was arrested in March after arriving on a flight from Morocco to the Mauritanian capital Nouakchott using a fake passport.
The ICC has jurisdiction if a government is unable or unwilling to hold a fair trial for an accused. Human rights advocates say Libya lacks that ability.
“If the extradition reports are confirmed, the decision to send him to Libya — with its weak justice system and inadequate fair-trial guarantees — will inevitably delay justice for victims and could lead to violations of al-Senussi’s rights to a fair trial,” Mr. Marczynski said.
Human Rights Watch, a New York-based group, said the Libyan government must cooperate with the ICC.
“Such actions are crucial for Tripoli to demonstrate that Libya is in a new era marked by the rule of law,” said Geraldine Mattioli-Zeltner, international justice advocacy director at Human Rights Watch.
Seif al-Islam, who is in the custody of an independent militia in the western Libyan city of Zintan, has been held for more than a year without being charged. He has said that if he were executed after a trial in Libya it would be tantamount to murder.
“I am not afraid to die, but if you execute me after such a trial you should just call it murder and be done with it,” Mr. Gadhafi was quoted by lawyers as saying, according to documents submitted to the International Criminal Court.
In June, an ICC team was detained for more than three weeks after meeting Mr. Gadhafi. A Libyan official, who pretended to be an illiterate guard, had stopped an ICC lawyer from taking a statement from Mr. Gadhafi.
Mr. Gadhafi’s father was killed in the custody of rebel militias in his hometown of Sirte on Oct. 20.