KABUL, Afghanistan - Thirteen Afghan civilians, including four women and two children, were killed Saturday when a roadside bomb ripped through their van in the country's south, the government said.

The Ministry of Interior said the morning explosion occurred in Shamulzayi district of Zabul province.

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Also in the south on Saturday, two gunmen on a motorcycle killed Wakil Mohammad Khan, a member of the local council in Nahri Sarraj district of Helmand province, the interior ministry said.

Separately, NATO reported that a coalition service member was killed Friday in a roadside bombing in southern Afghanistan. No other details were disclosed.

In Kabul, about 500 demonstrators chanting "Death to the Pakistan military!" and "Long live Afghanistan!" protested against rocket attacks that have killed at least 36 civilians, including 12 children, along the eastern border with Pakistan in recent weeks.

The protest, organized by a group known as the National Participation Front, called on the international community to warn Pakistan against the attacks. Group director Najibullah Kabali accused the Pakistani army and intelligence service of launching rocket attacks on innocent people in Nangarhar and Kunar provinces.

Pakistan on Monday denied Afghan accusations that it fired hundreds of rockets into two eastern provinces in Afghanistan, killing the 36 civilians, including 12 children.

Pakistani army spokesman Maj. Athar Abbas said no rounds were intentionally fired into Afghanistan, but that some may have accidentally fallen onto the neighboring state's territory when security forces targeted militants carrying out cross-border attacks into Pakistan.

The back-and-forth accusations have further strained the troubled relationship between the two countries.