Najib Razak and his wife, Rosmah Mansor, were prevented from taking a flight on a private jet to the Indonesian capital of Jakartaon Saturday, Malaysia’s immigration department said.
Mr Najib had stated on Twitter hours earlier he intended to take a short holiday with his family, but the flight has fuelled rumours he was attempting to flee the country ahead of possible corruption charges.
After over four decades in politics and the recent election campaign, which was regrettably personal and perhaps the most intense in Malaysian history, I will take a short break to spend time with my family whom I have not seen enough of in recent years.
Following the shock defeat of his National Front coalition in Wednesday’s election, the 64-year-old has also agreed to step down as chairman of UMNO, the bloc’s largest party.
The National Front has governed Malaysia for most of the country’s modern history, being ousted from power for the first time in 61 years.
Mahathir Mohamad, 92, has been sworn in as the new prime minister following the victory of his centre-left alliance, in turn becoming the oldest leader in the world.
“We accept the people's verdict with an open heart,” Mr Najib said.
“Maybe this will be an opportunity for us to fix our weaknesses and shortcomings, although these are more a matter of perceptions than reality. God willing, UMNO will continue to live.”
Commentators have attributed the National Front’s loss in part to the growing scandalinvolving the 1MDB state fund.
The fund was started by Mr Najib when he came to power in 2009, but accumulated billions in debts and is now subject to investigations by authorities in several countries.
US investigators claim the former prime minister and his associates stole $4.5bn (£3.3bn) from the fund, of which $700m (£516m) found its way into his personal bank account.
Mr Najib has routinely denied any wrongdoing, while also taking steps to gag the press and sack his critics in government, including an attorney general and his deputy prime minister.
The new attorney general, Mohamed Apandi Ali, previously cleared Mr Najib in 2016, saying the money was a donation from the Saudi royal family that had mostly been returned.
New prime minister Mr Mahathir has insisted his government would not go on a witch hunt over the scandal, but said he would axe Mr Apandi if it was found he had hidden evidence of corruption.
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