Kuala Lumpur: Former Malaysian Prime Minister Najib Razak was arrested on Tuesday, three sources familiar with the matter told Reuters, amid an investigation into how billions of dollars went missing from a state fund he founded almost a decade ago.

Authorities picked up Najib from his home after serving him with a remand order, two sources close to the family said. One of the sources said Najib was expected to be charged in court on Wednesday.

Malaysia’s anti-graft agency also said Najib had been arrested, according to state news agency Bernama.

A Najib spokesman did not immediately have a comment. Najib has consistently denied wrongdoing in dealings with state fund 1Malaysia Development Berhad (1MDB).

Since his shock election loss to Mahathir Mohamad in May, Najib has been barred from leaving the country, quizzed by the anti-graft agency and had his personal and family houses searched as part of the 1MDB probe.

Mahathir said in an interview with Reuters last month that embezzlement and bribery with government money were among the charges that Malaysia was looking to bring against Najib, adding they had ‘an almost perfect case’ against him.

Founded by Najib in 2009, 1MDB is being investigated in at least six countries for alleged money laundering and graft.

Civil lawsuits filed by the US Department of Justice allege that nearly $4.5 billion was misappropriated from 1MDB.