U.S. officials watched with growing concern Friday as reports suggested Pakistan was massing troops to the India border. Such a move raises double-barreled worries: A possible confrontation between two nuclear powers and a shift by the Pakistani military away from battling the Taliban along its western Afghan edge.
"We hope that both sides will avoid taking steps that will unnecessarily raise tensions during these already tense times," said White House spokesman Gordon Johndroe.
U.S. military leaders have been urging both India and Pakistan to exercise restraint in the wake of the deadly Mumbai attacks that many believe originated with Pakistan-based militants.
On Friday, U.S. intelligence and military officials were still trying to determine if the reported troop movements were true, and, if so, what Pakistan's intent may be. And they cautioned that the reports may be exaggerated, aimed more at delivering a message than dispatching forces.
Officials spoke on condition of anonymity to discuss intelligence matters.
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U.S. defense leaders have been worried about a new flare-up between Pakistan and India ever since the coordinated terror attacks in India's financial capital of Mumbai last month that killed 164 people.
India has demanded that Pakistan arrest the perpetrators behind the Mumbai attacks. It says they are members of Lashkar-e-Taiba, a militant group widely believed created by Pakistani intelligence in the 1980s and used to fight Indian-rule in the disputed Kashmir region.
Adm. Mike Mullen, chairman of the U.S. Joint Chiefs of Staff, was in Pakistan twice this month, and as many as seven times in the past year. In recent meetings with senior Pakistani leaders he has urged restraint and encouraged both sides to find ways to work together.
One senior military official said Friday that the U.S. is monitoring the issue, but still could not confirm assertions from Pakistani intelligence officials that some 20,000 troops were on the move, heading to the Indian border.
A key concern for U.S. officials is that some of those troops may have been stationed along the volatile Afghan border, and were being diverted to the Indian side.
Defense Secretary Robert Gates and Mullen, who have both been in the region in recent weeks, have expressed the hope that Pakistan would stay focused on fighting militants in its mountainous northwestern Federally Administered Tribal Areas, or FATA.
Insurgents there have proved increasingly troublesome, launching attacks into Afghanistan, disrupting supply routes for the Afghan, U.S. and coalition militaries, and providing training and hiding places for the Taliban, al-Qaida and others. It also has long been suspected that al-Qaida leader Osama bin Laden has been hiding there.
Senior defense officials said the U.S. is watching the situation very closely since officials would prefer that the Pakistanis remain focused on battling insurgents within their own country, including along the border.
U.S. Military leaders in Afghanistan earlier this month said they had seen no indications that Pakistan was shifting its focus away from the Afghan border.
There was also no indication Friday that either Gates or Mullen had reached out to their counterparts in Pakistan since these latest reports had surfaced.
Johndroe added that, "We continue to be in close contact with both countries to urge closer cooperation in investigating the Mumbai attacks and in fighting terrorism generally."