The police started the search after Najib returned home from prayers at a mosque to mark the first day of the Muslim holy month of Ramadan.
Bernama also reported that condominium units at the luxury Pavilion residence, believed to be owned by Najib, were also raided by police officers.
Malaysia's prison authority released former Deputy Prime Minister Anwar Ibrahim from prison on Wednesdayon full pardon from the King, clearing the way for the now-ruling coalition's de facto leader to become prime minister within a few years.
Wednesday's scenes made it clear that Anwar - who said he had received congratulatory calls from around the world including old friend and former United States vice president Al Gore - had lost little of his star power.
Najib was once Mahathir's protege.
Malaysia held elections on May 9-their first elections in which an opposition coalition emerged victorious. His release clears the way for him to return to politics, but it is unlikely he will take over as prime minister anytime soon.
When asked if Abdul Gani had presented any documents pertaining to the 1MDB investigation, the Prime Minister said the former A-G only gave a verbal account. Gani led an investigation by multiple agencies into the scandal at the time, which was later closed after Najib was cleared of wrongdoing.
"It depends on the particular actions we can carry out to remove them from being part of the government", he said.
"The focus on corruption is important because we need to get back money which is still in Switzerland, the U.S., Singapore and maybe Luxembourg".
If true, it could be an ominous sign for Najib, who has already been barred from leaving the country and is expected to face prosecution.
Dr Mahathir said the money could not be claimed earlier because the previous government did not admit that it belonged to 1MDB.
He said the government is also committed to repaying any debts linked to the fund that it has guaranteed.
But his successor and former mentor, 92-year-old Mahathir Mohamad, instructed police to re-investigate the case and put Attorney-General Mohamed Apandi Ali on leave, over allegations he helped cover up the corruption scandal.
Malaysians were touched when a video of Anwar watching Prime Minister Tun Mahathir's swearing-in ceremony (which took place on 10th May) from inside a hospital began to circulate online.
It's officially one week into the brand new Pakatan Harapan (PH) government after a historic general election, and big changes are happening all around us!
The finance ministry said in a statement Wednesday that a 6 per cent goods and services tax introduced by Najib in 2016 to increase government revenues will be abolished June 1.