CNN said authorities told reporters the device was made of RDX, the same type of explosive used in the bloody terrorist assault in the city that killed more than 170 people last week.

The bomb was found at the Chhatrapati Shivaji Terminus, formerly known as Victoria Station, where four RDX bombs were disarmed last week. Investigators say it is possible that other devices still could be found.

Meanwhile, the Indian government continued weighing its response to the terror attacks, which have ratcheted up tensions with longtime rival Pakistan. Investigators believe the attackers trained in Pakistan.

Indian Foreign Minister Pranab Mukherjee told the local NDTV channel Tuesday his government would take "appropriate action."

India has already lodged a formal protest with the Pakistani ambassador and demanded Pakistan hand over fugitives members of the Lashkar-e-Toiba group, which has reputed links to al-Qaida.