At 6:30 am on Sunday, Yang Renyi, president of the No 37 Hospital of the People's Liberation Army, led a group of more than 30 medical professionals toward Baoxing, a county in Sichuan province's city Ya'an, which was damaged by the magnitude-7 earthquake on Saturday.

Before the disaster, it used to take an hour and a half to drive from Lushan county, the epicenter of the earthquake, to Baoxing. But by the time they set off, the road connecting the two counties was blocked by a landslide, leaving them only one choice - to go on foot.

Six hours later, they arrived at Lingguan, a town in Baoxing, and discovered that all the houses and buildings were damaged. More than 1,000 people were injured.