"It seems people from the [Shiite] Hazara community were the target," said senior police chief Abdur Razzaq Cheema.
The explosive device was hidden between sacks of potatoes, in Hazar Ganji, a fruit and vegetable market on the outskirts of the city
Hazara make up roughly 500,000 of Quetta's population of 2.3 million. They are so frequently targeted that they are given police protection at the market.
"The same happened today, there were police… guarding them when the blast occurred," said Mohsin Butt, provincial police chief for Balochistan
At least eight Shiites were among the dead, along with a paramilitary soldier and seven other people. Four troops who were guarding the market were among the wounded.
No group immediately claimed responsibility for the attack, but Hazaras have been frequently targeted by Taliban and members of the Islamic State armed group and other Sunni Muslim militant groups, in both Pakistan and Afghanistan, which borders Balochistan.