Zhengzhou passersby rescue woman, grandkids trapped in flooded car

At the same time, Lu Lianmeng, owner of a convenience store, noticed two missing calls from Liu in the chaotic scene while saving his stock from being inundated. Lu called back and learned the emergency.

"I called the neighboring hotel and the manager, Li Kunpeng, came with me and we rushed to the spot. There was limited time for us to get prepared and what we had was a kitchen knife," Lu was quoted by the Beijing News.

The torrential rainfall rapidly grew into fast-rising floodwaters. Outside Lu's convenience store, the water depth soon reached 1.6 meters.

Liu kept calling her mother and two children every five minutes and learned the flood water had soon risen to her mother's neck. "She was sitting on the armrest and holding the children who were frightened at that moment," Liu told the Beijing News.

"My mother told the two kids that they were playing a game called adventure in flood and someone will come to rescue them soon," she said.