Police in Mumbai have found 8kg of explosives in a bag left behind at the main railway station at the start of attacks across the city last week.
Anti-terrorism chief K P Raghuvashi said a bomb disposal unit had defused the devices.
The station was one of the places targetted in the attacks in which at least 183 people were killed and more than 300 wounded.
The attacks in Indian's financial capital stunned the country.
Thousands gathered on Wednesday in Mumbai for a rally, with many protesting at the government for failing to prevent the attacks.
FBI agents are helping Indian police to gather evidence about the attack.
US attorney general Michael Mukasey says the United States has jurisdiction in cases of violence against Americans abroad.
Six Americans were killed in the attacks.