BEIJING, June 7 (AP) -- Hundreds of students in an earthquake zone in southwest China started taking crucial university entrance exams in tents Thursday, state media reported.

Xinhua News Agency said about 700 students in Ning'er county near China's border with Laos started their make-or-break exams in 80 tents set out in rows at a high school.

The county in Yunnan province was hit by a strong earthquake early Sunday, killing three, injuring at least 300 and making tens of thousands homeless.

Xu Huaming, the county education bureau chief, was quoted as saying the one school in the county that is the test site this year was not seriously damaged, but there were worries about aftershocks.

"We believe we must ensure 100 percent safety for our students," Xu said.

Across China, about 9.5 million students are taking the two-day entrance exams, competing for 5.67 million spots, Xinhua said.