The wife of a suicide bomber who blew himself up at Medan police station this week was even more radicalised than her husband and had been planning a terrorist attack in Bali.

Police investigating the blast, at Medan police headquarters on Wednesday, have since arrested the dead man’s wife and are investigating her links to other terrorists, including her communication with a jailed female terror suspect.

In the video above: Suspected suicide bombing strikes Indonesia police headquarters

Police have yet to reveal the exact nature of the Bali plot or how advanced it was but authorities in Bali have stepped up security on the tourist island.

Police have seized documents and computer equipment and say that the wife was communicating on social media platforms about plans for a Bali terrorist attack.

A 24-year-old university student, Rabbial Muslim Nasution, blew himself up in the parking lot area of Medan police station. He died in the attack, captured on police CCTV cameras, and several police and civilians were injured, although none seriously.

Attacker's wife arrested

In the wake of the attack, police swooped on his Medan home, arresting his 22-year-old wife of three years, Dewi.

They are also hunting the pair’s mentor, a cleric, whose identity is known.

Indonesian National police spokesperson, Dedi Prasetyo, said Densus 88, the country’s anti-terror squad, had arrested Nasution’s wife.

“The perpetrator’s wife is identified as DA. DA is allegedly exposed (to radicalism) earlier than the perpetrator.

Chevron Right Icon 'They are planning a terrorism act in Bali.'

“And physically, DA has communicated with I, who is now serving a sentence in Medan women’s prison. And in the social media communications network, they are planning a terrorism act in Bali,” Dedi said.

North Sumatra deputy police chief, Mardiaz Kusin, said that the suicide bomber had, according to statements from his parents-in-law, exhibited different behaviour in the past six months.

Five homes raided

In the wake of the suicide bombing, police have raided five houses, including the dead man’s home. Found in some of the raids, were a bow, pipes and paper calling for an Islamic caliphate.

It is believed the bomb used in Wednesday’s attack was assembled at the home of the now wanted cleric.

If revelation of the plans for a terrorist attack in Bali is true, it shows that Bali remains on the radar of radicalists in Indonesia.

The last terror attack in Bali was 2005, when suicide bombers targeted beachfront restaurants in Jimbaran and another restaurant in Kuta, killing 20.

Four Australians were killed during the suicide bombers attacked three restaurants on the resort island. Credit: AP

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And in 2002, the Kuta nightclub bombings, by radical group Jeemah Islamiyah, killed 200 innocent people and two suicide bombers.

The three masterminds of that devastating attack were executed by firing squad in 2008.

Since then scores of terrorists have been rounded up and jailed but Indonesia continues to struggle with the large numbers of militants who have gone to Syria and returned, pledging allegiance to Islamic State.

Recent arrests

Last month a father and son with links to Islamic State were arrested in Bali, accused of plotting a terror attack on the holiday hotspot.

They were alleged to have arrows, bayonets and an airsoft gun and police said they were closely linked to another man, accused of stabbing Indonesia’s Chief Security Minister, Wiranto, a few days earlier.

The two men arrested in Bali were said to have pledged a baiat or oath of allegiance to now slain IS leader, Abu Bakar al Baghdadi.

And the couple involved in the Wiranto stabbing attack were members of the outlawed terror group, Jamaah Ansharut Daulah or JAD, which is linked to IS.

Police have yet to confirm whether the Medan suicide bomber and his wife are also linked to JAD but many analysts suggest this to be the case.

And police have denied that a shipment of explosives and detonators, caught trying to enter Bali earlier this year, was not related to terrorism but was for use in illegal fish bombing.

Chevron Right Icon 'It was not related to terrorism, but illegal fishing.'

“It was old news, February this year. It was not related to terrorism, but illegal fishing,” Banyuwangi police chief, Taufik Herdiansyah Zeinardi, said.