He said the president`s son was unharmed as his vehicle had already passed the spot where the device exploded hitting a rikshaw and the last vehicle of the convoy.
"The rikshaw driver, a 12-year-old child in the rikshaw and a passerby died at the spot while four police personnel of the security squad received minor injuries," he said.
Zahid Ullah, a senior police official confirmed the incident and said the president`s son owns a dairy farm in the area and is a frequent visitor. "The president`s son was the apparent target of the attack," he said.
Meerak Baluch, spokesman of the Baluch Liberation Army (BLA) claimed responsibility for the attack in a telephone call to AFP.
"We claim responsibility for the attack, it was in response to the military operation carried out in various areas of Baluchistan," he said.
Resource-rich Baluchistan is the largest of Pakistan`s four provinces, but its roughly seven million inhabitants have long complained they do not receive a fair share of its gas and mineral wealth.
Rebels began their fifth insurgency against the state in 2004, with hundreds of soldiers and militants killed in the fighting since then.
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