BANGKOK • Thailand's Deputy Prime Minister Prawit Wongsuwan has warned officials they risk facing malfeasance charges if they do not hunt down fugitive former prime minister Yingluck Shinawatra, after recent photos circulating on social media apparently showed she had been in London.

The Office of the Attorney-General had said on Tuesday that it had not requested her extradition yet, citing a lack of information about her whereabouts.

General Prawit said on Thursday that prosecutors, police and the Foreign Ministry must work together to track down Yingluck or face prosecution for malfeasance or dereliction of duty, The Bangkok Post reported.

Commenting on whether the photos of Yingluck had been released in order to shame Thai officials for failing to hunt her down, Gen Prawit said it was still not known if she was using a passport issued by another country.

Yingluck's Thai passports have been revoked by the Foreign Ministry. She fled Thailand last August, just before the Supreme Court issued a verdict in a criminal negligence case against her, stemming from her government's corruption-plagued rice-pledging scheme.

In September, she was sentenced in absentia to five years in prison for mismanaging the scheme.

Two photos apparently of Yingluck have been widely circulated on social media in the past month, showing her in London. Thai police have confirmed the authenticity of one of them, which shows her with another Thai woman outside the Harrods department store in London.

On Tuesday, Thai Foreign Minister Don Pramudwinai said Yingluck was in London and that his ministry was in contact with its British counterpart to try to locate her. But he declined to comment on whether Thailand was seeking to extradite her. Thailand and Britain have an extradition treaty.

Speculation has also been rife that Yingluck could apply for political asylum to stay in Britain after fleeing Thailand to escape imprisonment.

The Nation newspaper reported on Thursday, citing media reports quoting unnamed sources in Yingluck's Pheu Thai Party, that she was living in Britain on an entrepreneur visa, and has not received political asylum.

Party members, however, were quoted as saying that they did not have any further details about her location and legal status.