The temporary truce ended Tuesday but an overall lull in the country's grinding violence has largely held despite the latest attacks, raising hopes the militants and Kabul could soon start much-delayed peace talks.
Taliban fighters attacked a checkpoint in Parwan, north of the capital, early Thursday, said Waheeda Shahkar, spokeswoman to the provincial governor.
"The Taliban have also suffered casualties," Shahkar told AFP, saying seven members of the Afghan forces died.
District police chief Hussain Shah said Taliban fighters set fire to the checkpoint, killing five security force personnel. Two more were shot dead.
In the western city of Farah, Taliban gunmen mounted an attack on a police post, killing seven policemen, provincial police spokesman Mohibullah Mohib told AFP.
"Eight Taliban fighters were also killed in the clash that lasted for half-an-hour," he said, adding four policemen survived the attack.
The Taliban have not commented so far.
Thursday's attacks are the first such assaults Afghan officials have blamed on the Taliban since the end of the surprise ceasefire offered by the militants over the Eid al-Fitr festival.
Afghan security forces, however, carried out air strikes in the south on Wednesday that police said had killed 18 "militants".
According to Afghanistan's Independent Human Rights Commission, civilian casualties fell by 80 percent during the short truce.