http://in.news.yahoo.com/071025/48/6mdne.htmlWe extend our condolences to you, to the victims' families, and to all of the people of Pakistan," the senators wrote in the letter.
"We believe this devastating attack serves as a stark reminder of the need for effective security mechanisms for the protection of all candidates and their supporters (particularly, although not exclusively, Bhutto and members of her party)..."
The senators called on Musharraf to provide the level of security to Bhutto offered to any former Pakistani prime minister.
They suggested the use of government bomb-proof vehicles and jamming equipment to protect Bhutto and other political leaders from roadside bombs.
The senators also said they were "troubled" by allegations "well founded or not" of potential links between extremist forces and current or retired military or intelligence officials.
"We urge you to ensure that any individual involved in (or alleged to have been involved in) past political action against Bhutto and her supporters be excluded from any part of the former Prime Minister's security detail."