Two suicide bombers have detonated explosives inside the headquarters of the main police station in the southern Afghan city of Kandahar on sunday.

Two policemen were killed and 29 people wounded in what is the latest violence to hit the country.

The blasts occurred just hours after a suicide bomber blew himself up in an attack on an Italian convoy in western Herat but there were no casualties.

Meanwhile a US military statement says U.S.-led soldiers, backed by air support, and Afghan police have killed more than 20 Taliban fighters in two separate clashes.

US forces killed more than 10 insurgents during an operation in the southeast province of Khost on Saturday.

And in the southern province of Helmand militants lost 10 men in an assault on a police post while four police were wounded.

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