A grenade exploded in a car outside a US embassy warehouse in the centre of Indonesia's capital in a botched attack that killed one of the occupants, police said.
"It was a grenade which was to be thrown at a warehouse owned by the US embassy but exploded in the car," Indonesian National Police Chief Mr Da'i Bachtiar told reporters.
He said there were four men in the car. One was captured and two escaped.
"With one arrested we hope we can reveal more information on who is behind this group or this movement," Mr Bachtiar said.
Indonesia, the world's most populous Muslim nation, has been criticised by some neighbours as dragging its feet in the global battle against terror. Some analysts claim it does not want to alienate its Islamic majority, most of whom are moderate Muslims.
In June, Indonesian authorities arrested an Arab, Omar al-Faruq, and turned him over to the United States. He has been linked to Osama bin Laden's al-Qaeda network and plans for attacks on US interests in the region.