At least three police stations in the state of Negeri Sembilan in southern peninsular of Malaysia have received mails which threatened to kill eight Malaysian high ranking officials including its prime minister, Najib Tun Razak.
The ninth person named in the letter, however, was not a Malaysian but the foreign minister and state counselor of Burma.
The threatening letter also attached with mugshot pictures of Suu Kyi and other eight Malaysian leaders.
Malaysian Inpector-General of Police, Khalid Abu Bakar, who himself was named in the letter, said his officers would conduct an investigation to identify whether the letter was a threat or a kind of mischief.
Malaysian authorities have arrested dozens of IS supporters including bomb makers and those who intended to join IS fighters in the Middle East.
At least two Malaysians were killed after they volunteered as suicide bombers in Syria and Iraq.
In June, the relatively peaceful Muslim majority country was shocked by an IS bomb attack which injured eight drinkers at a pub at Puchong, not far from Kuala Lumpur, the capital city of Malaysia.
While Suu Kyi is seen by some Burmese nationalists as too lenient in handling the issue of Rohingya in Arakan State, some newspapers in Malaysia, however, criticize her for being 'silent' on the issue.
Some Malaysian sympathizers equated Rohingya as 'Palestinian of Southeast Asia', referring to the conflict between Israel and Palestine in the Middle East. - Reporting from Kuala Lumpur, Malaysia by Thomas Chong