A powerful bomb explosion has claimed the lives of at least four children in the troubled east-central region of Afghanistan, according to officials, Press TV reports.

Local Afghan officials said the deadly incident took place in Sayed Abad District of Maidan Wardak Province on Thursday.

A spokesman for Hayatullah Hayat, the provincial governor of Maidan Wardak, said that the casualties were caused after the bomb exploded near a site where children were playing.

The attack comes as Afghan children are bearing the brunt of the ongoing violence in Afghanistan. A recent UN report shows that the death toll among Afghan civilians, especially children, has increased dramatically due to widespread violence in the war-ravaged country.

Separately, at least two civilians were injured after a magnetic bomb attached to a police vehicle went off in a district of the Afghan capital Kabul.

Elsewhere, in the eastern province of Laghman, at least five Afghan policemen were killed after Taliban militants ambushed a convoy of security forces.

Sarhadi Zwak, the spokesman for the Laghman governor, confirmed that the convoy came under fire from a group of heavily- armed militants in Mehtar Lam, the provincial capital on Thursday afternoon.

Also in the early hours of Thursday, a senior police officer and his brother lost their lives after suspected Taliban militants sprayed them with bullets during a security patrol in the troubled southern city of Kandahar.

Taliban militants have intensified their terror campaign against the government as well as civilians since they launched the so-called spring offensive in late April.

The militant group was removed from power after the United States and its allies invaded Afghanistan in 2001, but many areas in the country are still witnessing insecurity as a result of militant activities.