A homicide bomber trying to blend in with street beggars exploded himself near a top intelligence official in a crowded part of the capital early Wednesday, killing four people and wounding 12, police said.

The bomber apparently targeted the investigations chief of Afghanistan' intelligence service, said deputy police chief Gen. Zulmay Khan.

The explosion went off near Kabul's main market place, killing four people and injuring 12, Afghanistan's intelligence service said. No members of the intelligence service were hurt or killed, officials said.

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The attack's apparent target, Kamulladeen Khan Echekzai, is a powerful Afghan elder from the southern city of Kandahar, the Taliban's former power base when it ruled Afghanistan from 1996-2001.

An intelligence official, speaking on condition of anonymity because of agency rules, said authorities believe Echekzai was targeted because he knows details of top Taliban leaders suspected of operating from Pakistan.

The attack in Kabul came one day after a homicide bomber on foot disguised in an army uniform blew himself up outside a police station in Helmand province, killing four police.

Violence in Afghanistan has soared over the last year, and officials expect spring and summer to bring more homicide and roadside attacks.

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