PEREIRA, Colombia (AFP) — Colombia’s earthquake rescue efforts entered what officials called the “final phase” on Wednesday, as rescuers searched for signs of life beneath collapsed buildings before the critical first 72 hours came to an end.

The magnitude 7.4 quake, the strongest to hit Colombia this century, has killed 265 people, injured more than 3,500 and left almost 500 missing, according to local authorities.

In Cali and Pereira, emergency crews prepared to work through a third night with their bare hands, cranes and sniffer dogs, stopping not to rest, but to listen for signs of life.

Colombia’s newly installed president has declared the disaster an “economic emergency” and announced three days of national mourning.

“We will do what is necessary,” president Abelardo de la Espriella said in a statement, vowing to “emerge again as a country and as a society”.

According to official figures, more than 11,000 dwellings have been destroyed and thousands of families have been rendered homeless.

Many have already spent consecutive nights outdoors, either because their homes were damaged or because they feared aftershocks.

Many Colombians have mobilised to help, bringing water, food and supplies to affected neighbourhoods, while long lines formed outside blood donation centres.