Iran on Saturday hanged three men in public accused of involvement in the bombing of a Shiite mosque that killed 25 people, an official said, branding them "terrorists" and "enemies of God."
Iran also summoned Pakistan's ambassador Mohammad Bakhsh Abbasi over the deadly attack after Sunni rebels reportedly claimed responsibility, the official IRNA news agency reported.
The executions were carried out near the mosque in southeastern Iran which was devastated by Thursday's bombing, said Hojatoeslam Ebrahim Hamidi, justice chief of Sistan-Baluchestan province.
At least 125 people were also wounded in the powerful blast caused by a suicide bomber at the Amir al-Momenin mosque in the Sistan-Baluchestan provincial capital Zahedan during evening prayers.
"The terrorists Haji Noti Zehi, Gholam Rasoul Shahi Zehi and Zabihollah Naroui were hanged at 6:00 a.m. near the Amir al-Momenin mosque in public," Hamidi told the official IRNA news agency.
"They confessed to illegally bringing explosives into Iran and giving them to the main person behind the bombing," he added.
"They were convicted of being "mohareb" (enemies of God) and 'corrupt on the earth' and acting against national security," Hamidi said.
He said the trio had been arrested before Thursday's bombing but had confessed that they had provided the explosives for the mosque bombing.
"They were tried and they had court-appointed legal representation," he said.
The three men, he added, had also been charged with "direct involvement" in the bombing of a Revolutionary Guards bus in 2007 in which 13 people were killed, the bombing of Al-Ghadir mosque in Zahedan in February this year which caused no casualties and "some other bombings."
Iran summoned Abbasi after Iranian state television quoted pan-Arab channel Al-Arabiya as reporting that the Jundullah (Soldiers of God) group said it was behind the mosque attack.
Sistan-Baluchestan has for several years been the scene of a deadly insurgency by Jundullah, a group of Sunni rebels headed by Abdolmalek Rigi and which strongly opposes the government of predominantly Shiite Iran.
The province has a substantial Sunni minority and lies on a major narcotics-smuggling route from Afghanistan and Pakistan.
Jalal Sayah, the province's deputy governor said on Friday that the three men arrested over the incident were "hired by America and the agents of the arrogance."
Officials usually use the term "global arrogance" to refer to Iran's arch-foe the United States.
State Department spokesman Ian Kelly denied emphatically that Washington was behind the attack, saying the U.S. does "not sponsor any form of terrorism in Iran."
The chief of the Iranian armed forces, General Hassan Firouzabadi, in comments carried Saturday on the state television website, accused Britain and "Zionists" of involvement in the bombing.
"We should not forget the role and the plot of the British who in the past 200 years tried to divide Sunnis and Shiites," the general said.
State-run television, meanwhile, showed footage of funeral ceremonies on Saturday for those who died in the bombing.
Thousands of women and men clad in black gathered in front of the Amir al-Momenin mosque hours after the hangings carrying coffins draped in Iranian flags and banners bearing the name "Fatima al-Zahra," the daughter of the Prophet Mohammed.
At the time of the suicide bombing, the mosque was crowded with devotees mourning the death of Fatima, a revered figure in Shiite Islam.
Those at Saturday's funerals, according to IRNA, shouted, "I will kill he who killed my brother," and "Death to Wahhabis" - referring to followers of a fundamentalist Sunni strand of Islam as practised in Saudi Arabia.
Iran's supreme leader Ayatollah Ali Khamenei had on Friday urged restraint and called on Sunni clerics to "take a firm stand in loathing the corrupt ones who commit such crimes in the name of defending Sunni adherents."
He added that Shiite clerics should prevent "thoughtless and angry reactions."