Islamic State (IS) was behind a series of explosions and gun attacks in the capital Jakarta, an IS-linked news agency and police have said.
According to BBC News, at least two civilians and five attackers died in the assaults, described as an attempt to mimic the deadly Paris attacks.
Security forces battled militants for hours, with the attacks centering on a major business and shopping district.
It follows warnings late last year that Islamists were planning a major attack.
Indonesian President Joko Widodo has called on his country not to be defeated by “these acts of terror”.