EXCLUSIVE: These young Australians survived Morocco's deadliest earthquake in decades.

Oli Finkelstein was celebrating his 21st birthday on a rooftop bar in Marrakech, when he felt a slow rumble.

The Sydney student and his friend, Jack Smith, assumed it was a van going past the building.

Then their table started shaking and someone screamed 'earthquake' from the street below. Everyone around them scrambled towards the exit. 

"The building [we were in] felt unstable and shook hard," they told Mamamia. "The building opposite us lost its second story wall, and we watched it crumble."

The young Australians were in Morocco on Friday night, when the 6.8 magnitude earthquake struck, killing more than 2,500 people and injuring even more.

It was the strongest earthquake to hit the area in more than a century.

Knowing there might be an aftershock following the earthquake, Oli and Jack ran to find an open space. It was chaos.

"The streets were narrow, about four metres wide, as everyone tried to stay in the middle to avoid any falling debris," they said.

"People, bikes and cars raced through the dust... [there were people] with gashes on their head from being hit," they said.

"Minutes later, we were out in the square. Families phoned relatives to make sure they were safe, and we waited for an aftershock that did not come."

They said the entire thing was a "pretty scary experience".

"We ended up just trying to help, asking people if they were hurt, and buying sweets to give kids as they were the most shook."

Oli and Jack's accommodation wasn't affected and both of them are safe. They are some of the lucky ones.

Image: Supplied.

Image: Supplied.

The earthquake's epicentre was 72 kilometres southwest of Marrakech. 

Remote villages in the Atlas Mountains were hit the hardest by the quake. Those who survived are struggling to access food and water; many are still missing.

In Moulay Brahim, a village 40 kilometres south of Marrakech, residents described how they dug the dead from the rubble using their bare hands.

On a hillside overlooking the village, residents buried a 45-year-old woman who had died along with her 18-year-old son.

As one man retrieved possessions from his damaged home, he said he believed people were still buried nearby.

"They didn't get the rescue they needed, so they died. I rescued my children and I'm trying to get covers for them and anything to wear from the house," he said, per AAP.

In the badly hit village of Amizmiz, residents watched as rescuers searched for a man and his son. "One of them might still be alive," said a retired builder.

The team recovered only bodies.

Image: Getty.

After an initial response that was described as too slow by some survivors, search and rescue efforts appeared to speed up on Monday, with tent camps appearing in locations where people had spent three nights outdoors.

A video filmed by Moroccan outlet 2M showed a military helicopter flying over an area close to the epicentre, dropping sacks of essential supplies to isolated families.

With much of where the quake hit in hard-to-reach areas, authorities have not issued estimates for the number of people missing.

It was the country's deadliest earthquake since 1960, when a tremor was estimated to have killed at least 12,000 people.

Morocco has accepted offers of aid from Spain, the UK, the United Arab Emirates and Qatar, who have sent search-and-rescue specialists. 

King Mohammed VI called for prayers for the dead to be held at mosques across the country, while Moroccans fled to hospitals and medical centres to donate blood to help those injured.

- with AAP.

Donate to those affected through this GoFundMe here.

Feature image: Supplied.