Afghan security officials inspect the scene of Sunday's suicide bombing near a meeting between the Nangarhar governor and Taliban militants.
Kabul, Afghanistan CNN  — 

What was supposed to be a day of ceasefires turned into a day of carnage. Again.

Sunday marks the last day of Eid al-Fitr, the holiday celebrating the end of the Muslim holy month of Ramadan.

In honor of Eid, the Afghan Taliban announced a three-day truce – except against foreign forces – to coincide with the Afghan government’s 10-day ceasefire for Eid.

But on Sunday, a suicide bomber attacked near the Nangarhar governor’s compound, killing at least 18 people and wounding at least 49, provincial spokesman Attaullah Khoghyani said.

The bombing took place while Gov. Hayatullah Hayat was meeting with Taliban members as part of the Taliban’s ceasefire, which ended at midnight.

There was no immediate claim of responsibility for Sunday’s attack.

But it came just a day after another suicide bombing in Nangarhar province killed 25 people – including civilians and Taliban members. ISIS, which is not party to any ceasefire, claimed responsibility for that attack.

The differences between the Taliban and ISIS

It’s not surprising that ISIS claimed responsibility for Saturday’s attack that killed Taliban members. The two groups have been butting heads in their quest for dominance in Afghanistan.

Back in 2015, Taliban deputy leader Mullah Akhtar Mohammad Mansoor wrote an open letter to ISIS chief Abu Bakr al-Baghdadi, warning ISIS to keep out of Afghanistan and stop “creating a parallel jihadist front,” according to the Central Asia-Caucasus Institute research group.

While both the Taliban and ISIS are Sunni insurgent groups, they have very different goals. ISIS is trying to establish a global caliphate through a global war.

“By contrast, the Taliban’s ambitions are local and aim to set up a ‘pure and clean Islamic state in Afghanistan,’ ” the CACI said.

Complicated attempts at peace

The Taliban have inflicted frequent violence in Afghanistan, with the ultimate goal of taking over and imposing its strict interpretation of Islamic law. The group controlled Afghanistan until its 2001 ouster by the US-led coalition that invaded following the 9/11 attacks.

Current Afghan President Ashraf Ghani first spoke about the possibility of a ceasefire with the Taliban in February, when he said the government was willing to recognize the Taliban as a legitimate political party as part of a potential agreement.

And over the past few days, Afghan journalists, students and diplomats have reported unusual scenes of peace between Taliban members and Afghan forces and civilians. Images showed handshakes and hugs in many parts of the country.

Purported Taliban militants and Afghans embrace Saturday in Ghazni during a three-day truce for Eid.

CNN cannot independently verify those images, but a freelance journalist confirmed he saw similar scenes in Logar province on Friday and Saturday.

Afghan diplomat Zardasht Shams tweeted Friday, “Interesting images from across Afghanistan on the eve of Eid Day #ceasefire Afghan Army & Taliban hugging each other. May this ceasefire sustains forever.”

And a photo tweeted by an Afghan news correspondent showed what appeared to be a Taliban fighter and an Afghan service member taking a selfie.

Taliban’s ceasefire ends

As Eid al-Fitr ends, so did the Taliban’s truce Sunday night. And militants will pick up their weapons once again.

Kabul city police spokesman Hashmat Stanikzai said some unarmed Taliban had entered the Afghan capital Saturday. They handed over their weapons at the entrance – and their arms to be given them back when they left the city, he said.

Despite reports that the Taliban’s ceasefire might be prolonged, Taliban spokesman Zabiullah Mojahid told CNN on Sunday, “we have no intention to extend that.”

Ehsan Popalzai reported from Kabul; Holly Yan reported and wrote from Atlanta. CNN’s Laura Smith-Spark contributed to this report.