Twenty suspected militants including 13 foreigners have been arrested, police said today, adding to a list of hundreds detained in recent years accused of having links to terror groups.

The country has been on high alert since gunmen linked to Islamic State launched multiple attacks in Jakarta, the capital of neighbouring Indonesia, in January 2016.

The suspects were arrested in a counter-terror operation carried out in four states between Nov 30 and Dec 15, inspector-general of police Mohamad Fuzi Harun said in a statement.

They include a 50-year-old Filipino suspected of recruiting his countrymen here to join up with the Abu Sayyaf, a militant group notorious for kidnappings and beheadings in the southern Philippines.

The man, who has been living in the country since 2016, was believed to be a cousin of late Abu Sayyaf leader Isnilon Hapilon, an intelligence source told Reuters.

Hapilon, the Islamic State's anointed "emir" in Southeast Asia, was killed in October by Philippine troops in Marawi city, where he had led a five-month siege.

Police also arrested an Indonesian, suspected of being a leader of Jamaah Ansharut Daulah, a pro-Islamic State alliance of Islamic militants, he said.

The man was involved in a July 2017 bombing in Bandung, Indonesia, before travelling to Malaysia to escape arrest, Fuzi said.

"The suspect... planned to raise funds in Malaysia before departing for Syria to join up with Islamic State," he said.

A 46-year-old former teacher was arrested in Sarawak in connection with a plan to attack a beer festival in Kuala Lumpur, police said.

Three others had been arrested in October in connection with the plan.

- Reuters