The baby boy Zhang held in his arms in the photographs had been carried by his grandmother as they walked from their quake-hit home in a remote, mountainous village. Zhang offered to help the woman who was exhausted after walking for seven hours.

Zhang’s colleague Peng Ke took the pictures as Zhang was holding the baby and said he wanted to “record great moments during the rescue”.

Zhang was later publicly revealed to have been saved by firefighters himself after his family’s house collapsed in the Sichuan earthquake in May 2008, one of the deadliest on record in China, and which killed nearly 90,000 people.

Sichuan earthquake death toll rises to 82

Zhang was a Primary One student when the 2008 quake struck. He remembered the firefighters who came to build tents for his family and sent daily supplies like instant noodles to them.

“At that time, I decided to be a firefighter when I grew up and to rescue people like they did,” Zhang said.

Zhang, now in his early 20s, only just became a firefighter in May this year. After the pictures went viral on mainland Chinese social media he was affectionately dubbed “Brother Wenchuan”.

“It’s not a big deal. This is my responsibility,” Zhang said of the media attention. “My colleagues are all Brother Wenchuans.”

The two-month-old baby he was holding is the youngest known survivor of the earthquake.

In another coincidence delighting Chinese social media - the boy’s father is also a firefighter. It has been revealed that the baby’s father was working in another region when the quake struck.

The pictures of Zhang with the baby have generated an outpouring of admiration from mainland internet users.

“Thank you Brother Wenchuan,” wrote one person.

“The legacy of this love is so touching!” another commented.

“A kid saved by a firefighter later saved a firefighter’s kid,” a third commenter wrote.