A suicide bomber attacked a collecting of Taliban and Afghan security officials who had announced dueling cease-fires and were meeting on Saturday to celebrate the end of Ramadan fasting season in Nangarhar, officials said.
At least 26 people were killed and more than 50 wounded in the attack in the eastern city, including members of the militant group and civilians, officials said. The toll was expected to rise.
Dozens of unarmed Taliban militants had entered Afghan cities on Saturday to celebrate unprecedented overlapping cease-fires announced by both sides in recent days.
On June 7, President Ashraf Ghani announced an eight-day, unilateral cease-fire with the Taliban, a strategic move seen as a trust-building measure to encourage the militant group to conduct peace talks.
Days later, the militants declared that they would halt operations against Afghan forces for the three days of the Muslim festival Eid al-Fitr. The Taliban statement did not acknowledge the government’s cease-fire, but the two were scheduled to overlap for three days.
Analysts saw the moves as an attempt to inject life into a lackluster, long-struggling peace procedure. Over the past few years, the United States has increasingly embraced a political settlement as the only end to the long Afghan war.
But ahead of the cease-fires, the carnage continued, with suicide bombers striking a government building in the Afghan capital, Kabul, on Monday, killing at least 17 people and wounding at least another 31.
A Kabul police spokesman, Hashmat Stanekzai, said that the suicide bomber on foot had struck outside the Rural Rehabilitation and Development Ministry as employees were leaving work, according to The Associated Press.
No one immediately claimed the attack.
Another government office, in the eastern city of Jalalabad, was bombed that day, but no casualties were reported. A third bomb elsewhere in the eastern Nangarhar Province killed one person after detonating prematurely.
Even as news of the latest suicide bombing broke on Saturday, Mr. Ghani made an address to the nation saying his government would extend its cease-fire and called on the Taliban to do the same, according to local media reports.
It was not immediately clear if Mr. Ghani was aware of the bombing attack in the east when he made his address.
The Islamic State, which also has adherents in the country, has made no cease-fire announcement. The extremist group has claimed suicide bombings in the capital, and is also active in Nangarhar Province.
And even alongside its cease-fire announcement, the Taliban statement said international forces in the United States-led NATO coalition would still be targeted.
In an announcement marking the end of the fasting month of Ramadan, the group told “American invaders” to leave Afghanistan, assured the people of a bright future under Islamic rule and said it had already liberated “vast areas” of the country.
The Taliban leader, Sheikh Haibatullah Akhundzada, said in the statement that Afghans’ salvation lay in “American and other occupying forces” leaving, and he repeated a call for talks with the United States.
“If the American officials truly believe in a peaceful end to the Afghan imbroglio, then they must directly present themselves at the negotiation table,” Mr. Akhundzada said.
The Taliban are fighting United States-led NATO forces and the American-backed government to restore sharia, or Islamic law, after their ouster in 2001.