Civil society activists demonstrate outside the Greek Embassy, calling on the Greek government to grant political asylum to Maria Efimova, a Pilatus Bank employee who ignited a political scandal in Malta when she became a source for investigative journalist Daphne Caruana Galizia who was murdered last year, in Ta' Xbiex, Malta March 27, 2018. REUTERS/Darrin Zammit Lupi

ATHENS (Reuters) - Greece’s Supreme Court ruled on Thursday against the extradition of a whistleblower at the center of a Maltese corruption scandal, judiciary sources said.

Malta has issued two extradition requests for Maria Efimova, a Russian who stirred a political scandal over allegations of wrongdoing at Maltese-registered Pilatus Bank.

Daphne Caruana Galizia, an investigative journalist killed by a car bomb in October 2017, had identified Efimova as the source of internal bank documents.

These, Caruana Galizia said before her death, indicated that Michelle Muscat, wife of Maltese Prime Minister Joseph Muscat, owned a secret company in Panama. The Muscats have both denied the accusations.

Efimova left Malta last year with her family and turned herself in to Greek police in March. She was arrested under the warrant for alleged misappropriation of funds, accusations that she denies.

A lawyer representing her said in April that Efimova feared for her life if she returned to Malta.

That month a lower court also rejected the extradition request, but a Greek prosecutor appealed the ruling, taking the case to the Supreme Court.

Efimova was employed for three months in 2016 by Pilatus Bank and is accused by the bank of embezzlement. She denies the charges.