A sharp aftershock registering 5.3 on the Richter scale rocked rural areas around Iran's third city Tabriz on Tuesday just days after twin temblors caused deadly devastation, Iranian scientists said.
The new quake struck just 13 kilometres (eight miles) from Varzaqan, market town for a string of villages levelled by Saturday's tremors, Tehran University's Seismological Institute said.
The aftershock was powerful enough to spark panic in Tabriz, with staff streaming out of offices, the Fars news agency reported.
Earlier on Tuesday, two people were pulled out alive from the rubble of Saturday's quakes after enduring 72 hours buried in the debris.
The two were plucked from the smashed remains of their home after being detected by search dogs, state television and the official IRNA news agency reported, citing emergency workers.
IRNA said the pair, both in good health, were saved in a village near Varzaqan, northeast of Tabriz.
The hamlet was one of hundreds flattened by Saturday's twin quakes measuring 6.4 and 6.3 on the moment magnitude scale that killed 306 people and injured 3,000, according to an official toll.
Explore further: Deciphering clues to prehistoric climate changes locked in cave deposits