Three drones were used in residential areas during the Pakistani attack on Iran, Iranian reports said on Thursday.
The ISNA news agency reported that 10 Pakistani citizens were killed and four residential buildings were destroyed.
Pakistan attacked targets in Iran early on Thursday morning, apparently a retaliation for an earlier attack by Iran on Pakistani territory.
The attacks in Sistan and Baluchestan Province were aimed at extremists, the Pakistani Foreign Ministry announced.
In a statement, the Pakistani secret service also confirmed the use of drones as well as missiles in the military strike and named hideouts of the separatist groups Balochistan Liberation Army and Balochistan Liberation Front as targets.
Balochistan, also spelt Baluchestan, is a region spread across parts of Iran, Pakistan and Afghanistan that is home to the Baloch ethnic group.
Earlier on Tuesday, Iran attacked targets of the extremist Sunni group Jaish al-Adl (Army of Justice) in Pakistan. According to Pakistan, two children were killed in the attack.
Surrounding countries fear an escalation between Iran and the nuclear power Pakistan. China and Turkey have signalled their willingness to mediate.