The Lisbon appeals court ruled that Wright had Portuguese citizenship and will not be extradited, his lawyer said  [AP]

Lisbon's appeals court has refused to extradite a convicted US murderer who was arrested after 41 years on the run on the grounds that he was now Portuguese, his lawyer has said.

George Wright, a 1970s African-American activist who escaped from a murder sentence in the state of New Jersey and successfully left the country on a hijacked airplane, was arrested in September in Portugal.

"The Lisbon appeals court ruled that he had Portuguese citizenship and will not be extradited," his lawyer Manuel Luis Ferreira told the AFP news agency on Thursday.

Wright, 68, had been living for 20 years under the name of Jose Luis Jorge dos Santos,  and was married with two sons.

"He is now free," the lawyer said of Wright, who had been held under house arrest pending the court's ruling on a US bid to have him extradited.

The decision could be appealed in a higher court, but only if an individual or institution petitions as a civil party, Portugal's Lusa news agency said, citing a judicial source.

Plane hijack

The US Federal Bureau of Investigation (FBI) had been searching for Wright since his August 1970 escape from Bayside State Prison in New Jersey, where he was jailed for a 1962 murder.

For two years, Wright disappeared into the Black Liberation Army, an underground activist group that members said was fighting for the collective liberation of African-Americans.

Then, on July 31, 1972, he was among five adults who hijacked a Delta flight flying from Detroit to Miami.

The hijackers demanded a $1m ransom for the passengers and when this was paid, they forced the plane to fly to Boston where it refuelled and took on another pilot hostage, then crossed the Atlantic to Algeria.

The hijackers sought asylum there.

Although the plane and money were seized by the Algerians and returned to the US, the hijackers were only briefly detained. In May 1976 French police captured four of the gang, but not Wright.

Wright's lawyers said he got his new identity from Guinea Bissau, a former Portuguese colony in West Africa, in the 1980s.

The day after Wright was caught on September 27, Michael Ward, who heads the FBI division in Newark, New Jersey, said his arrest proved that law enforcement agencies' commitment was unwavering, "even after 40 years".