KARACHI (AFP) - A bomb targeting one of Pakistani President Asif Ali Zardari's senior personal security officers killed at least three people in Karachi on Wednesday, police said.

The blast came in the middle-class Guru Mandar neighbourhood of central Karachi, close to an office of Zardari's Pakistan People's Party, which rules southern Sindh province.

"It was a bomb blast and at least three people were killed and 10 others were wounded," said senior police official Tahir Naveed.

Another police official, Usman Bajwa, said Bilal Sheikh, President Zardari's top personal security officer in Karachi, was among those killed in the bombing.

"I can confirm that Bilal Sheikh has expired," he added.

Mr Naveed said the bomb was so powerful that it shattered the bulletproof vehicle in which Mr Sheikh was travelling.

President Zardari and Prime Minister Nawaz Sharif "strongly condemned" the attack, state media said.