Of them, up to 41 people have died in a suicide bombing and gun battle, which injured 150 others, at a police training centre in Gardez, Paktia's provincial capital.
At least 30 others have been killed in car bombings in neighbouring Ghazni province.
The initial double attack in Paktia occurred when fighters attacked the regional police headquarters at around 9am local time (04:30 GMT) on Tuesday in Gardez, less than 161km from the capital, Kabul.
The attackers used a truck and an armoured vehicle stolen from security forces to carry out the bomb attack, which left 41 people, including police chief Brigadier-General Toryali Abdiani, dead and more than 100 wounded, Hidayatullah Hamidi, Paktia's deputy governor, told Anadolu Agency.
According to officials, a large number of Paktia University students and civilians, who were present near the police headquarters to collect their identity cards and passports, were among the victims.
General Murad Ali Murad, deputy interior minister, said in Kabul that 21 civilians were among the dead in the Paktia blasts.
In a statement, the interior ministry said seven men took part in the attack: two carried out the bombings while the rest of the attackers engaged with the police in armed clashes.
Special police units later overpowered the remaining five attackers, the statement said.
|Up to 150 people were injured in the Gardez attack [Farid Zahir/AFP/Getty Images]|
In a statement on Twitter, Zabiullah Mujahid, the Taliban spokesman, claimed the Paktia attack.
He said the special police unit was the primary target; up to 450 police officers were living in the headquarters at the time of the attack.
Bordering North Waziristan, one of Pakistan's seven semi-autonomous tribal areas or "agencies", Paktia in Afghanistan is the birthplace of the Taliban's Haqqani Network.
Pakistan's military regained control of North Waziristan from the Pakistan Taliban after an offensive launched in mid-2014 that lasted until the end of 2016.
The Ghazni provincial administration said in a statement released on Tuesday that fighters blew up an armoured vehicle at the entrance of the Andar district administration in the early hours, and later engaged in a gun battle.
Up to 30 people, mostly policemen, were killed, the statement said.
The Taliban's Mujahid gave a higher death toll, saying 44 police officers died in the Ghazni attack while a large cache of arms and ammunition was also seized.
|Gardez, the capital of Paktia, has seen regular Taliban activity [Faridullah Ahmadzai/AFP/Getty Images]|
Afghanistan's deputy interior minister said the "enemies and their foreign backers" - without identifying them - were under immense pressure from Afghan and allied forces, which was why they had chosen this time for such attacks when efforts for peace talks were gaining momentum.
General Joseph Dunford, chairman of the US joint chiefs of staff, told the Senate Armed Services Committee earlier this month that he believed Pakistan's powerful Inter-Services Intelligence (ISI) agency maintained links to armed groups.
"It is clear to me that the ISI has connections with terrorist groups," he said, referring to groups that are actively engaged in the Afghan conflict, including the Afghan Taliban and the Haqqani network.
In response, the Pakistani military said it is the job of intelligence agencies to maintain such connections, but rejected the notion that it supported groups such as the Afghan Taliban.