WASHINGTON  With two missile strikes over the past week, the Obama administration has expanded the covert war run by the Central Intelligence Agency inside Pakistan, attacking a militant network seeking to topple the Pakistani government.

The missile strikes on training camps run by Baitullah Mehsud represent a broadening of the American campaign inside Pakistan, which has been largely carried out by drone aircraft. Under President Bush, the United States frequently attacked militants from Al Qaeda and the Taliban involved in cross-border attacks into Afghanistan, but had stopped short of raids aimed at Mr. Mehsud and his followers, who have played less of a direct role in attacks on American troops.

The strikes are another sign that President Obama is continuing, and in some cases extending, Bush administration policy in using American spy agencies against terrorism suspects in Pakistan, as he had promised to do during his presidential campaign. At the same time, Mr. Obama has begun to scale back some of the Bush policies on the detention and interrogation of terrorism suspects, which he has criticized as counterproductive.

Mr. Mehsud was identified early last year by both American and Pakistani officials as the man who had orchestrated the assassination of Benazir Bhutto, the former prime minister and the wife of Pakistan’s current president, Asif Ali Zardari. Mr. Bush included Mr. Mehsud’s name in a classified list of militant leaders whom the C.I.A. and American commandos were authorized to capture or kill.