At least 17 people were killed in an apparent terror attack on a funeral procession in eastern Afghanistan on Sunday. Another 13 people were injured.

Initially, officials stated a suicide bomber was responsible for the attack, but later said the explosive device was attached to a motorcycle and detonated remotely.

"The explosion was caused by a motorcycle bomb," Nangarhar governor spokesman Attaullah Khogyani told the AFP news agency.

While no terror group immediately claimed responsibility for the bombing, the blast took place in the eastern province of Nangarhar, which is considered a stronghold of the "Islamic State" (IS) militia.

Read more: Dozens dead after IS attack on Shiite mosque in Kabul

The victims, all of them civilians, were marking the passing of former regional governor. The officials reportedly died of natural causes.

In a Sunday statement, Afghanistan's Taliban denied any connection with the apparent terror strike.

IS commits string of attacks across Afghanistan

The funeral bombing is just the latest deadly attack to hit Afghanistan this month. Earlier this week, a blast claimed by the IS killed 41 people in a Shiite cultural center  in Kabul.

Read more: Why is 'Islamic State' targeting Shiites in Afghanistan?

On Christmas day, six civilians were killed in an attack near a compound used by Afghanistan's intelligence agency. IS also claimed responsibility for the attack.

A week before that, IS militants stormed an intelligence training compound in Kabul.

While a total number of civilians deaths in 2017 was not immediately available, the year looks set to become one of the deadliest since the US toppled the Taliban regime in 2001. UN data says over 8,000 civilians were killed in the first nine months of 2017. In 2016, the year-end death toll reached 11,418.

dj/rc (AFP, AP, dpa, Reuters)