The new prime minister, Mahathir Mohamad, has vowed to probe Najib's alleged roll in pilfering billions of dollars from the state investment fund 1MDB.
Commercial crime director Amar Singh Ishar Singh told local media that investigators were still trying to determine the value of the haul. In all, 284 boxes of luxury handbags as well as 72 bags of jewelry and cash were seized.
"Our personnel checked these bags and discovered various currencies including; Malaysian ringgit and US dollars; watches, and jewelry in 72 bags," Singh said. "Exactly how much jewelry, I would not be able to say, because we know that we confiscated bags containing jewelry and the amount of jewelry is rather large."
Singh said the valuables were seized late on Wednesday in raids on six properties linked to the former premier, including the prime minister's office and official residence as well as four private residences.
Najib's wife, Rosmah Mansor, is known for expensive shopping trips abroad.
1MDB investigation gains momentumThe raids that began late Wednesday are linked to an investigation into the 1MDB scandal relaunched after Mahathir became prime minister last week.
Over the weekend the 92-year-old prime minister barred Najib, his wife, and others linked to 1MDB from leaving the country.
The raids raised speculation that Najib could be arrested after Mahathir suggested his former ally could be charged over the 1MDB scandal soon.
Najib has been accused of corruption and the mismanagement of 1MDB, which he established in 2009. He denies any wrongdoing.
Six foreign countries are also investigating the former prime minister and his associates at 1MDB. US investigators say at least at least $4.5 billion (€3.8 billion) of the fund's assets were stolen and laundered.
Nearly $700 million had appeared in Najib's bank account. A Malaysian investigation into Najib was ultimately dropped in 2016.
Meanwhile, Mahatir has put the attorney general that cleared Najib of wrongdoing on leave and relieved the country's treasury head, who was also the 1MDB chairman, of his duties.
Political shake-upMahathir, who ruled from 1981 to 2003, came out of retirement to spearhead a four-party alliance that won a surprise victory in the May 9 elections, ending nearly 60 years of rule by the Basiran National coalition.
Popular frustration over the 1MDB affair is widely believed to have led to Najib's loss.
On Wednesday, Mahatir's foe-turned-ally Anwar Ibrahim was released from prison.
Read more: Malaysia's Anwar Ibrahim: from prisoner to prime minister-in-waiting
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cw/sms (AFP, dpa, AP, Reuters)