Kabul: Three separate accidental explosions in the Afghan capital have left six people dead and more than 20 wounded, including some counternarcotics police, officials said on Monday.

A policeman dropped a rocket-propelled grenade, which exploded as his unit set off from Kabul yesterday on an opium poppy eradication mission north of the city, said Interior Ministry spokesman Zemarai Bashary.

The policeman was killed and at least eight were wounded, said Ahmad Zia Aftali, chief of the hospital where the injured were taken for treatment.

However, another policeman who witnessed the blast said in all more than 15 were hurt.

Also yesterday, three children died and two others were wounded when an old artillery shell they were playing with exploded, Bashary said.

Another police official, Sayed Ekramudin, said two civilians were killed and 13 others were wounded in an explosion on Sunday at a refuse dump in the city's northern outskirts.

After decades of war, Afghanistan remains littered with unexploded ordnance.

Insurgent gunfire

Also yesterday, a civilian helicopter was hit by insurgent gunfire in mountainous eastern Afghanistan, forcing it to make an emergency landing at a Nato military base, the alliance force said.

No one was injured in the incident in Kunar province, which borders Pakistan, Nato's International Security Assistance Force (ISAF) said.

"The helicopter made a landing at an ISAF base, in central Kunar, after taking machine gunfire from an unknown number of insurgents," ISAF said in a statement.

"The aircrew inspected the aircraft and found one bullet hole that did minor damage to the helicopter."

Insurgents battling the Afghan army and its international allies have shot at several military helicopters, most often missing.

In an attack, seven ISAF soldier were killed in May 2007 when a helicopter crashed in southern Afghanistan.