KARACHI, Pakistan — KARACHI, Pakistan -- Former Prime Minister Benazir Bhutto made her first public foray yesterday since a deadly attack Thursday on her homecoming celebration, signaling that she will not be deterred from mingling with supporters as her party begins its parliamentary election campaign.
But her visits, to a Karachi hospital where many of those wounded in Thursday's suicide bombing were being treated and afterward to a Sufi shrine for prayers, were brief, unannounced and tightly controlled, in contrast to the carnival-like, open-air procession that preceded the attack.
Bhutto received a phone call yesterday from U.S. Secretary of State Condoleezza Rice, who expressed sorrow over the attack, which killed more than 135 people and wounded hundreds, Bhutto aides said.
Speaking to journalists at the headquarters of her Pakistan Peoples Party, Bhutto acknowledged that she and her supporters would have to "modify our campaign to some extent" because of the attack.
But she added: "We will continue to meet the public. We will not be deterred."
In her 15-minute stop at Karachi's Jinnah hospital, Bhutto visited the bedsides of several men who were injured while acting as volunteer security guards for her convoy. Police officers and party faithful took the brunt of the powerful blast, which came as Bhutto's convoy was in the ninth hour of a trip from Karachi's airport to the city center, moving at less than 1 mph because of the enormous crowd. Bhutto, who was in her armored vehicle, escaped injury.
After visiting the hospital, Bhutto offered prayers at a shrine in Karachi's poverty-stricken Lyari neighborhood, a traditional party stronghold. As word of her appearance spread, a crowd gathered and chanted: "Prime Minister Benazir."
No group has come forward to claim responsibility for the bombing, though at least one radical faction issued threats before her return. Bhutto said at a news conference hours after the attack that she believed that Islamic militants had carried out the suicide bombing, with the possible complicity of present and former officials in the government of Gen. Pervez Musharraf, the country's president.
The government has denied any responsibility and said that everything possible was done to protect Bhutto.
The former prime minister sharpened her rhetoric yesterday, decrying "closet supporters of militants and al-Qaida ... determined to stop the restoration of democracy because they see it as a threat to the structure of militancy they have put into place."
Aides to Musharraf, who are engaged in power-sharing negotiations with Bhutto, have tried to avoid overt criticism of the former leader, but Interior Minister Aftab Khan Sherpao, himself the target of a suicide bombing in April, said yesterday that investigations of such attacks are a painstaking affair and suggested that it was unrealistic to expect immediate results.
Bhutto said the government should enlist foreign help in carrying out the investigation.
"We want the government of Pakistan to seek assistance from the international community -- they have the anti-terrorism expertise to investigate attacks of this nature," she said.
U.S. officials declined to say whether the FBI or other investigators stationed in Pakistan have been asked to provide help.
The White House declined to comment yesterday on Bhutto's visit to the hospital.
"As we said immediately following the attack, we strongly condemn this violence, mourn the loss of innocent life and continue to stand in solidarity with the people of Pakistan as they fight extremists," said spokesman Rob Saliterman.
Members of Congress, speaking on Sunday talk shows, expressed concerns about the violence.
"We should be very worried about what's happening in Pakistan," Rep. Peter Hoekstra, a Michigan Republican and member on the House Intelligence Committee, said on CNN's Late Edition with Wolf Blitzer. "Not that it means that it's on a path to an imminent collapse, but Pakistan is critical in us being successful in taking out and defeating radical Islamists and al-Qaida."
Karachi continued burying its dead yesterday. More than three dozen bodies remained unclaimed at the city's main morgue, some because they were so badly mangled that they could not be identified.
Many at the rally had come from distant parts of the country, and family members came to Karachi to search for their bodies after realizing that relatives were missing.
Laura King writes for the Los Angeles Times.