NEW DELHI (Agencies) - US Secretary of State Condoleezza Rice on Wednesday warned that India should ensure its response to Pakistan over the Mumbai attacks does not provoke unintended consequences, reports Indian media. "Any response needs to be judged by its effectiveness in prevention and also by not creating other unintended consequences or difficulties," Rice said at a joint Press conference after meeting India's External Affairs Minister Pranab Mukherjee. The visiting US Secretary of State met her Indian counterpart in New Delhi and the latter shared with her the evidence on the Mumbai terror strikes pointing towards involvement of "elements" based in Pakistan. Refusing to rule out the option of a possible military action against Pakistan, Pranab said that all options were open following last week's terrorist attacks on Mumbai. Terrorism was the biggest menace to global peace and tranquillity since Cold War, he said. Although Rice said she refused to "jump to any conclusions about who is responsible," US intelligence officials have privately supported India's accusations. Rice repeated her call for Pakistan to cooperate with the probe, and noted that US citizens were also among the victims of the attacks. "Pakistan needs to act with urgency and with resolve and cooperate fully and transparently," said Rice. "The response of the Pakistan government should be one of cooperation and action. That is what we expect and we have been sending that message," said Rice, who is expected in Pakistan on Thursday (today). "This message has been conveyed and will be conveyed (to Pakistan)," she said adding that extremists have done "great damage" to Pakistan too. The meeting "was about the assistance US can offer," Rice told reporters after the 20-minute talks at the North Block. "That message will be delivered to Pakistan," said Rice, who was expected to fly to Islamabad. The US Secretary of State emphasized that Pakistan had a special responsibility to ensure that perpetrators of the strikes are brought to justice. "We are going to work very closely to get to the bottom of the investigation," she said. Responded sharply to President Asif Ali Zardari's comment that the terrorists who attacked were "state-less", Rice, who also met Indian Prime Minister Manmohan Singh and will be in Islamabad on Thursday (today) to discuss the Mumbai attacks, said rejected his (Zardari) contention that "non-state actors" could be behind the terror strikes and demanded that Islamabad take "direct and tough" action against terrorists. "The fact is sometimes non-state actors operate from the confines of the state. There has to be very direct and tough action (by Islamabad) against them," she said. She bluntly told Pakistan that non-state actors were "still a matter of your (Pakistan) responsibility that somehow relates to your territory". "Pakistan has to act transparently, fully and urgently," said the Secretary of State who was rushed here by President George W Bush in view of rising tensions between India and Pakistan over the Mumbai attacks. The Secretary of State also expressed the possibility of the terrorists being affiliated to the Al-Qaeda, given the magnitude and sophistication of the attacks. "The US has experience in counter terrorism," she said offering US help. Speaking at a joint news conference with visiting Rice, Pranab said there was "no doubt" that the gunmen had come from Pakistan and were coordinated from Pakistan. He said that India demands that the terrorists who perpetrated the attacks were arrested and brought to New Delhi from Pakistan. He further said that India would take strongest possible measures to ensure that there was no repetition of attacks like Mumbai terror strikes. Rice also met India's Home Minister P Chidambaram and discussed the situation arising out of the terror attacks in Mumbai. "What action will be taken by the government will depend on the response we have from the Pakistan authorities," he said, referring to India's formal demand that Pakistan hand over terrorist suspects and crack down on cross-border militancy. "I am expecting the response, (and) after obtaining the response, whatever the government considers necessary to protect its territorial integrity, safety and security of its citizens, the government will do that," he added. The Indian Minister claimed what he called terrorists who had hit Mumbai were being controlled from Pakistan. "I informed Dr Rice that there is no doubt the terrorists were individuals who came from Pakistan and whose controllers are in Pakistan," Mukherjee said. He said India wanted to see that "the terrorists and organisations who perpetrated these attacks are arrested and brought to justice". "We expect all friendly governments and the international community to ensure that this happens." Condoleezza Rice also called on Leader of Opposition L K Advani at his residence in the capital. Rice held a 40-minute discussion with Advani and assured all cooperation from the US. It is learnt that the issue of involvement of a neighbouring country was also brought up during the meeting. Earlier talking to reporters ahead of talks with Indian leaders, US Secretary of State Rice said India, Pakistan and others must act with "urgency and resolve" to bring the Mumbai attackers to justice. She urged Pakistan to respond "swiftly and transparently" to New Delhi's accusations that the gunmen came from across the border. According to Doordarshan TV channel, sources said the Bush Administration is angered by the use of Pakistani soil for attacks in Mumbai as the Zardari government had assured it of not allowing such things to happen. The US feels "let down" by Pakistan as the country is getting major portion of financial support from Washington and hence has the reason for mounting pressure on it, sources added. Meanwhile, Indian police claimed that they had discovered and defused explosives at Mumbai's main railway station, left by suspected gunmen who struck the city last week. The situation was "under control" and a bomb disposal unit had defused the devices, anti-terrorism chief KP Raghuvashi told AFP.