PEOPLE dug frantically with their bare hands through the debris of collapsed buildings in Myanmar’s second-largest city today, two days after a massive earthquake killed more than 1,700 people and left thousands buried.

The 7.7 magnitude quake, with an epicentre was near Mandalay, hit at about noon on Friday, bringing down scores of buildings and damaging other infrastructure like the city's airport.

Relief efforts have been hampered by damaged roads, collapsed bridges, interruptions to communications and the challenges of operating in a country torn by civil war.

The search for survivors has been primarily conducted by local residents without heavy equipment, moving rubble by hand and with shovels in 41°C heat, with only the occasional tracked excavator to be seen.

This afternoon, a 5.1 magnitude aftershock triggered screams from people in the streets, before the makeshift rescue operation continued.

Many of Mandalay’s 1.5 million people spent the night sleeping on the streets, either because they had been made homeless by the quake, which also shook neighbouring Thailand and killed at least 17 people there, or because they feared that the continuing aftershocks might cause structures damaged to collapse.

Cara Bragg, the Yangon-based manager of Catholic Relief Services in Myanmar, said: “It’s mainly been local volunteers, local people who are just trying to find their loved ones.”

Rescue efforts from the outside must use the damaged roads as the airports at Mandalay and the capital Naypitaw have both been put out of service.

A convoy of 17 Chinese lorries carrying critical shelter and medical supplies was expected to reach Mandalay by road today, after its 400-mile journey was slowed by clogged roads and traffic diverted from the main highway to avoid earthquake damage.

But the window of opportunity to find anyone alive is rapidly closing. 

Most rescues occur within the first 24 hours after a disaster, after which the chances of survival diminish as each day passes.

Beyond the earthquake damage, rescue efforts are complicated by the bloody civil war across much of Myanmar, including in quake-affected areas. 

In 2001, the military seized power from the elected government of Aung San Suu Kyi, sparking what has since turned into significant armed resistance.

Tom Andrews, a special rapporteur for the United Nations Human Rights Council in Myanmar, urged the military to immediately call a ceasefire.

“Aid workers should not have to fear arrest and there should be no obstructions to aid getting to where it is most needed,” he said.