Two Afghans were killed and six others were wounded Wednesday morning when a motorcycle bomb went off in Sangin district of the country's southern province of Helmand, an official said.

"A bomb attached to a motorbike was detonated in Sangin district bazaar when an Afghan National Army (ANA) convoy was passing by the area. One civilian and one ANA soldier were killed in the incident which took place at round 10:30 a.m. local time there," a provincial government spokesman Omar Zhwak told Xinhua.

The injured included three civilians and three army personnel in the province, 555 km south of national capital Kabul, he added.

No group has claimed responsibility for the attack so far. However, the Taliban insurgent group has intensified attacks since late April when they launched an annual rebel offensive against Afghan and about 100,000 NATO-led forces stationed in the country.

Up to 2,499 civilians had been killed or injured since January this year, the UN mission in the country announced on Tuesday, attributing 74 percent of the casualties to the Taliban and other militant group attacks.

On Tuesday evening, Taliban carried out a car bombing near the gate of the Supreme Court in Kabul, killing 17 civilians and injuring nearly 50 others.