Inspector-General of Police Khalid Abu Bakar told CNN that a grenade attack on June 28 at a nightspot near Kuala Lumpur, the country's capital, was carried out on the orders of a Malaysian Islamic State fighter in Syria, Muhammad Wanndy Mohamed Jedi.
While there were no fatalities in the attack, eight people were injured. Most of the people at the nightclub, called Movida, were there to watch the Spain-Italy Euro 2016 match.
Khalid said 15 people have been arrested in wake of the attack, including the two men who lobbed the bomb at Movida. Those arrested also included two policemen.
"One of the policemen was picked up for harboring ISIS elements, while the other was arrested for involvement in robberies to collect funds for ISIS," he told CNN.
Khalid added that Muhammad Wanndy had ordered attacks on prominent Malaysians, including Prime Minister Najib Razak, police counter terrorism division senior assistant director Ayob Khan Mydin Pitchay, and Khalid himself.
Khalid, who declined to release more details, said investigations are ongoing and that police expect to make more arrests.
The police had initially ruled out terrorism as the reason for the attack on Movida, believing instead that the motive was a business rivalry or a dispute among patrons. However, Muhammad Wanndy later claimed on Facebook that the attack had been carried out by ISIS followers.
The Malaysian police have foiled nine ISIS plots to attack Malaysia since the declaration of the Islamic State in Iraq and Syria in 2014.
Terrorism expert Dr. Rohan Gunaratna, head of the International Center for Terrorism Research and Political Violenc
e (ICPVTR) at the S. Rajaratnam School of International Studies
(RSIS) in Singapore, said in an analysis
the attack in Malaysia, despite counter terrorism operations, shows ISIS ideology has spread and established a regional presence in Southeast Asia.
Andrin Raj, regional director of International Association for Counterterrorism and Security Professionals Center for Security Studies Southeast Asia, told CNN that threats against the country will continue.
"The modus operandi will be suicide attacks as well as explosive/IED attacks as it is easier to conduct an attack and difficult to prevent," he said.
Raj added that while police are calling it ISIS operations in the sense that it has been given approval and authority by ISIS, the terror group's presence has not yet fully developed into actual ISIS cells.
"As of now, they are sympathizers. But the fact is, this will eventually grow into ISIS cells," he said.