Yingluck Shinawatra, who was ousted in 2014, failed to appear for a court verdict
Thailand's ex-PM Yingluck Shinawatra is claimed to have fled to Singapore after she missed a court hearing where she could have been jailed for 10 years.
Ms Shinawatra - who headed Thailand's government between 2011 and 2014 before being removed by the country's Constitutional Court - failed to appear for a verdict in her criminal trial on Friday.
It has fuelled speculation she has joined her brother, fellow former premier and ex-Manchester City owner Thaksin Shinawatra, in self-exile.
A senior source in Ms Shinawatra's political party told AFP: "She is definitely no longer here, she is likely in Singapore now.
"She left on Wednesday."
Current Prime Minister Prayut Chan-o-cha, the head of a military junta who toppled Ms Shinawatra's government in a 2014 coup, told border officials to increase inspections at routes out of the country after his predecessor's court no-show.
"I just learned that she did not show up," he said. "I have ordered border checkpoints to be stepped up."
He added: "If she's not guilty she should stay and fight the case.
"If she's not here, what does that tell you? Will she still say that she didn't get justice?"
Thailand's Supreme Court issued an arrest warrant for Ms Shinawatra after she missed the hearing, although the politician's lawyer said she could not attend because of illness.
"I was told at 8am that she was sick from Meniere's disease and felt vertigo, so she asked the court to postpone," her lawyer Norawit Larleng told reporters outside the court.
He added that he did not know if Ms Shinawatra was still in Thailand.
A verdict has now been postponed until 27 September.
The 50-year-old is accused of negligence over a rice subsidy programme that she oversaw while in power, estimated to have cost Thailand $17bn (€14bn).
Ms Shinawatra pleaded innocent and denounced the charges against her as politically motivated.
The court battle is the latest fight between the Shinawatra family, who are popular among the country's rural poor, and the royalist military elite.
Thousands of Ms Shinawatra's supporters, observed by police, gathered outside the court on Friday.
Her billionaire brother, who was ousted from power in a previous military coup in 2006, has lived in self-imposed exile since fleeing a corruption conviction in 2008.
Mr Shinawatra is believed to use a Montenegrin passport, after his Thai document was revoked, to travel between homes in Dubai, London, Hong Kong and Singapore.