National And World News

WASHINGTON (CBS) ― U.S. officials are worried about a possible surge in violence between India and Pakistan after the bloody attacks in Mumbai that killed at least 195 people, including six Americans. To ease tensions, intelligence officials are searching urgently for clues that might identify the attackers even as Indian officials claim "elements in Pakistan" were involved.

FBI agents were preparing to fly to India to investigate the bloody attacks in the Indian financial capital as the State Department warned U.S. citizens still in the city that their lives remain at risk.

A U.S. counterterrorism official said some "signatures of the attack" were consistent with the work of Pakistani militant groups known as Lashkar-e-Taiba and Jaish-e-Mohammed that have fought Indian troops in the disputed Himalayan region of Kashmir and also are reported to be linked to al Qaeda.

But the official emphasized it was premature to pinpoint who was responsible for the attacks. Another official, specializing in counterintelligence, also cautioned against rushing to judgment on the origins of the gunmen who waged a two-and-a-half-day rampage through India's leading commercial center before being killed.

The U.S. officials spoke on condition of anonymity due to the sensitivity of the situation.

The U.S. Embassy in New Delhi on Saturday raised the death toll among Americans from five to six including at least three from a Jewish outreach center and a Virginia man and his 13-year-old daughter killed when gunfire erupted at a hotel restaurant. Embassy officials gave no details on the identity of the sixth victim.

Will Geddes, an international risk assessment specialist, told The Saturday Early Show that the attacks were the worst nightmare in terms of how terrorists operate. By targeting hotels, the terrorists were able to hit a wide swath of people. They hit the international community and they hit Indians, Geddes said.

India and Pakistan have fought two of their three wars over Kashmir. U.S. officials are concerned about a flare-up in animosity similar to one that occurred after Pakistani militants attacked the Indian parliament in December 2001, the officials said.

Underscoring those fears, Secretary of State Condoleezza Rice has called the foreign minister of India twice, along with Pakistani President Asif Ali Zardari, since the crisis began.

"There were very worrying tensions in the region," said Gordon Duguid, a State Department spokesman. "She was calling the president of Pakistan to get his read on how those tensions might be affected."

As U.S. officials worked to ease hard feelings between India and Pakistan, a tentative rapprochement between the two nuclear-armed rivals could hang in the balance.

Pakistan's ambassador to the U.S., Husain Haqqani, said in a statement that his country is "confronting the menace of terrorism with great vigor." Haqqani insisted "it is unfair to blame Pakistan or Pakistanis for these acts of terrorism even before an investigation is undertaken."

President George W. Bush pledged cooperation with Indian authorities and mourned the deaths of at least 195 people at the hands of gunmen.

"My administration has been working with the Indian government and the international community as Indian authorities work to ensure the safety of those still under threat," Bush said in statement Friday.

Bush was receiving regular updates, White House press secretary Dana Perino said Friday night. Senior administration officials were focused on ensuring that Americans were being helped in every way possible, she said.

Officials were working out the final details with Indian diplomats Friday for the departure of an FBI team, said U.S. authorities, who also spoke on condition of anonymity because of the delicate nature of the operation. A second group of investigators was on alert to join the first team if necessary.

U.S. officials were checking with Indian authorities and hospitals to learn more about the extent of casualties.

The State Department set up a call center for Americans concerned about family members who may be in Mumbai. The number is 1-888-407-4747.

(© 2009 CBS Broadcasting Inc. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. The Associated Press contributed to this report.)