A bomb exploded at Indonesia's Parliament building (search) on Monday, smashing windows but causing no casualties, police said Monday.

No one claimed responsibility for the blast, the latest in a series of smalls bombings in Indonesian since last year's devastating attacks on Bali (search) island.

"It was a bomb," said a senior officer who declined to be named.

The early morning blast caused minor damage to a ground-floor building at the complex in central Jakarta (search).

Last week, police confiscated a huge haul of explosives and detonators and arrested nine Islamic militants they said were planning terror attacks across the nation.

Last October, two bombs exploded on the tourist island of Bali, killing 202 people. The attack has been blamed on Islamic militants.

Since then, there have been several small blasts in Jakarta and other cities. Police have said most of these were the work of separatists from the country's westernmost Aceh province.