BAGHLAN, Afghanistan — A bomb struck a group of lawmakers Tuesday as they were being greeted by children on a visit to a sugar factory in Afghanistan's normally peaceful north. At least 28 people were killed, including five parliament members as well as children.

U.S.-backed President Hamid Karzai blamed "the enemies of peace and security," a euphemism often used for the militant Taliban. But such a spectacular attack could also have been the work of al-Qaida. The Taliban denied involvement.

Video obtained by AP Television News of the scene just before the blast shows schoolchildren, tribal elders and government officials lining the streets to greet 18 lawmakers as they were about to enter the sugar factory in Baghlan, a town about 95 miles north of the capital, Kabul.

Some of the children shook hands with the guests and one teenager handed red, pink and white roses to lawmaker Sayed Mustafa Kazimi — a former Afghan commerce minister and a powerful member of the opposition party National Front.

The teenager said loudly in the Afghan language of Dari: "On behalf of the Islam Qala school students, we welcome you here."

Moments later, Kazimi was dead.

"The children were standing on both sides of the street, and were shaking the hands of the officials, then suddenly the explosion happened," said Mohammad Yousuf Fayez, a doctor at Baghlan's main hospital.

The video does not show the explosion.

After the blast, the video shows dead and wounded schoolchildren on the ground. Shoes, sandals, hats and notebooks were scattered about.

Two men carried the bloody body of a boy by his limbs and put it on the hard-packed dirt. Men placed another body next to four others already laid out under a tree. Elsewhere, a body with a severed arm was lying amid rubble. Puddles of blood soaked the packed dirt around the scene of the bombing.

Many victims were taken to the hospital, their legs and faces stained with blood. The video shows a woman leaning over a child lying motionless in a hospital bed. A boy, his legs bandaged, cried on a gurney that looked to have been left in a hallway.

The video also shows an Afghan man holding the head of what he claimed was the suicide attacker, shouting "Look at this (expletive)! This is the guy who destroyed everything! This is the guy who killed us!"

Officials gave conflicting reports whether the attack was a suicide bomber or a planted bomb. If it is determined to be a suicide bomber, that would point strongly to al-Qaida or Taliban involvement

No one claimed responsibility for the attack, and a purported Taliban spokesman, Zabiullah Mujahid, denied the militant group was involved.

"The Taliban doesn't target civilians," he said.

Taliban attacks typically target Afghan and international security forces or government leaders but often kill civilians nearby. Most of their attacks are in the country's south or east. Taliban bombers have killed regional governors in the past, but never so many public figures at once.

The Ministry of Interior said at least 28 people were killed, one of the deadliest attacks of the year. But Mohammad Yousuf Fayez, a doctor at Baghlan's main hospital, said more bodies may have been collected from the site by families and not counted in the official toll. Earlier, a government official said 64 people had died.

At least 42 of the 81 wounded were schoolchildren, Fayez said. It was unknown how many children were among the dead.

Shukria Barakzai, a lawmaker, said 18 of the 249 members of Afghanistan's lower house of parliament had traveled to Baghlan, and that 13 were dead or "in danger."

Karzai confirmed the deaths of five lawmakers. Police officers and officials from the Department of Agriculture were among the dead.