Aid agencies are scrambling to respond after news that at least 700 people have died after an 8.8 magnitude earthquake struck the South American nation of Chile on Saturday.

As many as two million people have reportedly have been affected by the quake and subsequent tsunami.

There has been extensive damage to buildings and infrastructure – particularly in the city of Conception, the second largest in the nation which lies close to the epicentre of the quake, and in coastal communties where entire populations are feared lost.

Repeated aftershocks, some as strong as magnitude six, have continued to affect the area.

Chile’s President Michelle Bachelet has described the disaster as “a catastrophe of such unthinkable magnitude that it will require a giant effort (for Chile to recover from it)”.

The Red Cross says that water and electricity systems in the worst affected areas are not functioning and there are no operating hospitals in the cities of Conception, Talca and Curico.

Rioting has been reported and the government has sent the in army to bolster police.

The earthquake comes less than two months after a 7.0 magnitude earthquake devastated Haiti and left a death toll of more than 200,000. 

Madeline Wilson, emergency communications specialist for World Vision Australia, said in a statement that the Chile quake will present different challenges to those responding.

"Haiti was concentrated and that led to the challenge of tons of aid and hundreds of aid workers being sent into a small zone. This quake off the Chilean coast has potential to reach remote areas. It will take some time to assess the number of deaths and amount of damage."

Experts have suggested that the history of earthquakes in Chile – one of the latest, a 7.7 magnitude earthquake which struck the country's north in November 2007 – and the solid construction of buildings may have prevented many more deaths.