JAKARTA (Reuters) - The Indonesian authorities are investigating whether a suspected militant arrested last week was plotting an attack on the resort island of Bali, the police said.

Police found a bomb and "high (impact) explosive materials"during a raid on the suspect's house on the western island of Sumatra, according to the media.

The man, whom the police have yet to identify, was arrested on suspicion of having links with extremist group the Islamic State in Iraq and Syria (ISIS) and of being involved in planning a suicide bombing at a police station in the central Javanese city of Solo last month.

The Solo attack only killed the bomber himself and wounded one police official.

Mr Edy Hartono, chief of the counter-terrorism police unit, said police were looking into the suspected Bali plot. "It was still just a plan," he told Reuters, declining to elaborate.

The arrest in Lampung, Sumatra, was among a series of terrorism-related arrests across several cities in Indonesia last week as the authorities intensify a security crackdown in the world's largest Muslim-majority country.

Indonesia saw its first ISIS-linked attack in January when four militants mounted a gun and bomb attack in a busy commercial district in the capital Jakarta. Eight people were killed, including the militants.

Bali, a popular tourist destination, saw a number of attacks by homegrown militants in the early 2000s, the deadliest being a nightclub bombing that killed 202 people, mostly Australians.