Police in Indonesia say they have arrested 11 people they suspect of planning to attack Western targets.
Explosive materials and a bomb-making manual were found at some locations used by the militants - a recently-formed group, reports said.
Among the targets was the US embassy in the capital and a mining company.
A crackdown on Islamist militants followed the Bali bombings of 2002, but there have been several terror-related arrests in recent months.
The suspects were arrested after police raids on four locations.
The detainees are suspected of planning attacks against the US embassy in the capital Jakarta and the US consulate in Surabaya.
The offices of mining company Freeport-McMoran were also to be targeted by the group, according to police spokesmen.
The detainees reportedly belong to a relatively recently-formed militant group called the Sunni Movement for Indonesian Society (Hasmi).
It is not clear whether the group has any links with the older Jemaah Islamiah (JI) militant organisation, blamed for the Bali bombings which killed 202 people.
Earlier this month, Indonesia marked the 10th anniversary of the bombings with commemorations attended by Australian Prime Minister Julia Gillard and held amid tight security.
Since 2002, JI has been weakened by anti-terror operations but Indonesia has seen smaller-scale terror attacks by lone bombers and smaller groups in recent years.