Pakistan has moved hundreds of troops and tanks to its southern border with Afghanistan, according to witnesses.
A train carrying soldiers and tanks was seen heading to the border town of Chaman as Pakistani border officials said they had sealed the frontier with Afghanistan in case Osama bin Laden tries to sneak into the country to evade capture.
The officials said not even trucks bringing Afghan fruit to Pakistan from the Chaman border crossing were being allowed in. But trucks carrying relief goods were allowed to enter Afghanistan.