The bombs went off outside a sugar factory in the northern province of Baghlan as the lawmakers were about to go inside. The twin blasts struck school children, Afghan elders and government officials who had gathered to greet the visiting delegation of 18 lawmakers from the lower house, officials said.
At least 64 people were killed, said a government minister who asked not to be identified releasing information not yet made official. At least five members of parliament were among those killed, he said.
Shukria Barakzai, a lawmaker, said 18 of the 249 lower house parliamentarians had traveled to Baghlan province, and that 13 were dead or "in danger."
Baghlan lies about 150 kilometers (95 miles) north of Kabul.
If the death toll is confirmed, the attack would be the deadliest in Afghanistan since the 2001 U.S.-led invasion. Taliban bombers have killed regional governors in the past, but never have militants killed so many high-ranking officials in one attack.
The northern Afghan region where the blast happened is known for tensions between the mainly ethnic Tajik government leadership and remnants of the militant group Hezb-i-Islami, whose fugitive leader Gulbuddin Hekmatyar, an ethnic Pashtun, is allied to Osama bin Laden and al-Qaida but has denied organizational links.
Kamin Khan, a police official, said people "everywhere" were dead and wounded, including police, children, lawmakers and officials from the Department of Agriculture.
Among the lawmakers killed was Sayed Mustafa Kazimi, a former Afghan commerce minister and a powerful member of the Northern Alliance, said the lawmaker's secretary, Ahmadi, who gave only one name. Kazimi also served as the spokesman of the largest opposition group in Afghanistan, the National Front.
Interior Ministry spokesman Zemeri Bashary did not confirm the deaths of any parliamentarians, saying several had been taken to the hospital. He said the lawmakers were part of parliament's economic commission.
He said the government was trying to tally all the wounded and dead at the different hospitals.
He blamed the attack on the "enemy of Afghanistan, the enemy of the people of Afghanistan," a term commonly used here to refer to Taliban militants but that could also include other terrorist groups like al-Qaida.
The discovery of the submarine has unveiled a few "inconsistencies." For example, how can one explain the fact that the sub was found where it needed to be searched for from the start?
The TurkStream, which runs along the bottom of the Black Sea from Russia's Anapa to Turkey, will consist of two lines, each with a capacity of 15.75 billion cubic meters of gas a year