GUIXI, Jiangxi Province - More details were released on Tuesday regarding an auto accident in East China that killed 11 kindergarten students and devastated the families of the "left-behind" children involved.

The driver of the minivan, which belonged to a school and was overloaded with 15 children and two adults at the time of the accident, was speeding on a rural road undergoing repairs and plunged into a three-meter deep pond on its way to a kindergarten early Monday. Only four children and the two adults survived, police in the city of Guixi, Jiangxi province, said.

The latest probe results show that the children, aged 4 to 6, were students of the privately-run Chunlei Kindergarten in Binjiang Township. The school's principal, 35-year-old Zhou Chun'e, was driving the van on Monday.

Police said Zhou overloaded the van, which had a designed seating capacity of seven, and "drove improperly," resulting in the accident.

One of the tires of the van got caught in the unfinished road when Zhou was driving in excess of the speed limit. Zhou slammed the gas pedal, causing the van to veer off the road and into the pond, police explained.

Local officials disclosed a list of casualties. A Xinhua investigation found that most of the children lived with their aging grandparents as their parents have migrated to cities for work, a situation typical across China's vast countryside.

Tong Fuliang, who was working in a factory in neighboring Zhejiang province at the time of the accident, said he became frantic when he learned that his four-year-old son was involved in the accident.

"My legs shook so uncontrollably that I almost fell," said Tong Fuliang, adding that he and his wife rushed "like mad men" to the hospital where his son was being treated.

Their son, Tong Yongjie, was among the four survivors, but Tong Fuliang still broke down in tears in the hospital ward.

"I want to take him with me to Zhejiang. Though life might be bitter out there, it helps me feel calm with the family around," Tong Fuliang told Xinhua.

Tong Boliang, 59, felt a bit relieved because his grandson boarded a different van that day. (The two Tongs are not related.)

"If he was a bit late and took the second van, I might have missed him forever," said Tong Boliang.

He said his grandson is already in elementary school but, like many others who live in the area, the family pays 200 yuan ($32) a semester to use the Chunlei Kindergarten van to commute to school.

The government's investigation shows that the kindergarten, founded in 2004, has nine teachers and 95 students. A publicity official of Guixi maintained that the school was operating without proper licensing.

However, villagers have complained that there are few practical alternatives to unauthorized kindergartens for poor "left-behind" children.

Photos of mud-stained children's clothes, tiny shoes and school bags scattered on the bank of the pond have created a sensation online, with the public demanding that transportation safety be ensured for rural students.

Nineteen preschoolers and two adults died after the school bus they boarded -- a nine-seat van carrying 64 passengers -- collided head-on with a coal truck in Gansu province last November.

The accident garnered national attention, prompting authorities to order a school transportation overhaul, especially in rural areas where safety rules are not usually well-enforced.

In August, the Ministry of Education issued a circular urging local governments to establish a school bus safety management system, set a reasonable transition period and make detailed provisions in terms of school bus permissions, school bus drivers' qualifications and legal responsibilities.

The focus of the management work should be put on rural areas where schooling is beyond the reach of public transport and nearby schooling is not feasible, the circular noted.