(CNN) -- For Muslims around the world, Eid al-Adha is a time of celebration, marked by visits from far-flung relatives, gift-giving and elaborate feasts.
But this year, the joyous occasion Tuesday was marred by bomb blasts and deaths in violence-plagued Afghanistan and Iraq, and in civil war-wracked Syria.
In southern Afghanistan, a member of the NATO-led International Security Assistance Force died Tuesday after an attack by enemy forces, ISAF reported. ISAF did not identify the service member or the member's nationality.
Later Tuesday, the United Kingdom's Defence Ministry said that enemy fire killed a British soldier who was on patrol Tuesday in southern Afghanistan's Helmand province, northeast of the provincial capital of Lashkar Gah. It wasn't immediately clear whether this was the death that ISAF reported.
In the country's east, a bomb placed under a stage killed the governor of Logar province as he was delivering an Eid al-Adha speech inside a mosque Tuesday morning.
In addition to Gov. Mohammad Arsala Jamal, the blast killed four others and injured 15 more, the head of the provincial council, Abdul Wakil, told reporters.
Jamal, who also had Canadian citizenship, was an outspoken critic of insurgents in Afghanistan. Before he served in Logar, he had been governor of eastern Afghanistan's Khost province.
In Iraq, at least 11 people were killed and 26 others wounded when a bomb exploded outside a mosque in central Kirkuk, Iraqi officials said.
The bomb went off as worshippers were leaving the mosque, police said.
And in Syria, where a bloody civil war continues to claim lives daily, three children were killed in an explosion that anti-government activists blamed on President Bashar al-Assad's regime.
A revered observance
Eid al-Adha is considered one of Islam's most revered observances. It corresponds with the height of the Hajj, the pilgrimage to Mecca in Saudi Arabia that annually draws 2 million Muslims.
It commemorates when God appeared to Abraham -- known as Ibrahim to Muslims -- in a dream and asked him to sacrifice his son as an act of obedience. As Abraham was about to perform the sacrifice, God stopped him and gave him a sheep to kill in place of his son. A version of the story also appears in the Torah and in the Bible's Old Testament.
The four-day celebration is also known as the Feast of Sacrifice, or Greater Eid. It is the longer of two Eid holidays observed by Muslims. Eid al-Fitr, or Little Eid, follows the conclusion of the holy month of Ramadan.
CNN's Mohammed Tawfeeq from Atlanta and journalist Qadir Sediqi from Kabul, Afghanistan, contributed to this report.