KABUL, Afghanistan — A minibus carrying civilians in the western province of Herat hit a roadside bomb Tuesday, triggering an explosion that killed 16 civilians, including children and women, provincial officials said.

A provincial spokesman, Muhiuddin Noori, said the dead included 11 children and four women, a toll that underscored, despite U.S. claims of improved security, how dangerous Afghanistan has become for civilians.

A United Nations report released earlier this year said that civilian casualties had increased by 15 percent in 2010, with 2,777 civilians killed, the deadliest year for civilians since the U.S. first sent troops here in 2001. The trend likely has continued in 2011.

The report attributed 75 percent of those casualties to the Taliban.

President Hamid Karzai condemned the killing in a statement and called it an "inhuman and terrorist" act. "With such cowardly killing of civilians they proved that they won't even spare children and women's lives," the statement said.

The victims were all members of the same family, Noori said. They were returning from a wedding when their minibus hit the improvised explosive device in the Shindand district of Herat province.

Most civilian casualties are caused by suicide bombings or IEDS, the Taliban's weapons of choice.

The Herat explosion happened just hours after a suicide bomber in the southern province of Helmand rammed an explosives-laden car into the main gate of the police headquarters in the province's capital, Lashkar Gah.

A provincial spokesperson said that two civilians, including a teenager, were killed and another 26, including 10 police officers, were wounded.

(Zohori is a McClatchy special correspondent.)

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