Sept. 12 (UPI) -- Rescuers were working Tuesday to reach small mountain towns in Morocco close to the epicenter of Friday's earthquake, as the military began erecting field hospitals and attempting to provide aid with helicopters.
Government officials said at least 2,901 people have died, with 5,530 injured in the magnitude 6.8 tremblor.
Aid organizations said the catastrophe has left up to 300,000 people in need -- a huge challenge for relief efforts.
Search teams from Britain, Spain and Qatar joined the Moroccan military in an increasingly desperate effort to find and free any survivors trapped in the rubble of collapsed buildings.
Impassable roads and heavy damage were impairing efforts, said Moulay Hafid Alaouie, head of Morocco's Red Cross in Marrakech-Safi.
On Sunday, Morocco's King Mohammed VI declared days of national mourning and asked for spiritual aid from the nation's mosques, including prayers for the dead.
Al Jazeera reported Tuesday that some survivors said they feel abandoned by the North African nation's government, as authorities are focusing on larger communities. This is in part because it's unlikely that the rubble of homes made from mud bricks in smaller villages covers survivors since the nature of the material means there may be no air pockets.
Jesús Galindo-Zaldivar, a Spanish professor of geodynamics and expert on Morocco's Atlas Mountains, said the area is not known as geologically active, with earthquakes uncommon.
But, he wrote, "Stress from the plates pushing together has been building up deep underground for a long time."
Eventually, the stress was "too much for the fault to handle" and "it caused an earthquake."
Galindo-Zaldivar said there could be more danger to come.
"Other nearby faults might now be under extra stress, and they could produce smaller earthquakes known as aftershocks that might continue for months or even years."