The third blast late Saturday was in Quetta. It broke the windows of Federal Investigation Agency office but there were no casualties, Khan said.
A spokesman for the little-known Baloch Liberation Front, who identified himself as Colonel Doda, called the Quetta Press Club and claimed responsibility for two bomb blasts in Turbat.
Also late on Saturday 39 devotees were killed and scores injured in a powerful bomb blast at the memorial of a Sufi saint in the remote town of Fatahpur, around 300km from Quetta.
"The death toll has risen to 39 and 16 people are injured, some seriously," director of rural police Akbar Lasi told AFP on Sunday.
"Investigators have reached the site of the blast and are collecting evidence," Balochistan police chief Chaudhry Muhammad Yaqub told AFP.
"We are trying to ascertain whether it was a suicide bombing, because the body of a man close to the blast site had been ripped into small pieces," Yaqub said.