Five suspected Islamic State sympathisers have been arrested in Indonesia, a police spokesman said Tuesday, adding that authorities also confiscated bomb making materials.
The suspects -- a married couple and three other men -- were detained after a raid by anti-terrorism forces on three locations in the city of Bandung West Java, spokesman Yusri Yunus said.
Police claim the attackers were part of the IS-linked Jamaah Ansharut Daulah (JAD) network that has been blamed for a series of recent attacks in Indonesia including one in Jakarta in January 2016 that left four civilians dead.
"We found evidence in one of the suspects' houses. The evidence is a bomb made of chemical material," he told AFP.
Yunus said the group planned to attack the state palace, a local police headquarters as well as officers in the field.
Police allege the group got instructions on how to make the device from a blog post written by Bahrun Naim, an Indonesian who is fighting with IS in Syria.
Naim has been accused of directing a series of mostly-botched terror plots in his homeland in recent years.
Authorities in Indonesia, the world's most populous Muslim country, have been on heightened alert following several recent attacks claimed by Islamic militants.
In May suicide bombers killed three police officers at a bus station in Jakarta, while a gun and suicide attack in the capital in January last year that left four civilians and four assailants dead marked the first assault claimed by IS in Southeast Asia.
Anti-terror policemen stand beside goods seized from a house of suspected Islamist militants in Bandung, West Java province, Indonesia.
