Rescuers in Turkey and Syria battled bitter cold Tuesday in a race against time to find survivors under buildings flattened by an earthquake that killed more than 7,300 people.

Tremors that inflicted more suffering on a border area, already plagued by conflict, left people on the streets burning debris to try to stay warm as international aid began to arrive.

But some extraordinary survival tales have emerged, including a newborn baby pulled alive from rubble in Syria, still tied by her umbilical cord to her mother who died in Monday's quake.

"We heard a voice while we were digging," Khalil al-Suwadi, a relative, told AFP. "We cleared the dust and found the baby with the umbilical cord (intact) so we cut it and my cousin took her to hospital."

The infant is the sole survivor of her immediate family, the rest of whom were killed in the rebel-held town of Jindayris.

The 7.8-magnitude quake struck Monday as people slept, flattening thousands of structures, trapping an unknown number of people and potentially impacting millions.

Whole rows of buildings collapsed, leaving some of the heaviest devastation near the quake's epicenter between the Turkish cities of Gaziantep and Kahramanmaras.

The destruction led to Turkish President Recep Tayyip Erdogan declaring Tuesday a three-month state of emergency in 10 southeastern provinces.