Mourners had left more than 82,000 comments as of 9 pm on the last post of Qian Lingyun, one of the firemen, on Sina Weibo, China's Twitter-like micro-blogging service.
They also reposted the message more than 56,000 times. Qian's post contained six pictures showing him training at a fire station in Shanghai.
"It has been a tough year. There is another half year. I need to hold on," the 23-year-old wrote.
The other fireman, Liu Jie, was 20 years old. They had enrolled in December 2012.
One netizen wrote: "You explained to the world that the generation born after 1990 is courageous - not a crumbling generation. Thank you, my heroes."
Another comment read: "It's the valor of heroes like you that keep our homes safe. I give you my most sincere and honest tribute and salute."
A statement released by Shanghai's fire department on Friday said Qian and Liu served as pipemen on the mission to extinguish a blaze in a 13th-floor apartment in downtown Xuhui district around 2 pm.
A strong backdraft occurred when firemen were breaking down the apartment door. It was so powerful that it pushed Liu and Qian, who were holding hose nozzles, out of a window in the elevator lobby, the release said.
The two freefell onto the roof of an entrance gate and were pronounced dead at 2:20 pm.
The fire was put out at 3:57 pm. Ten people lived in the 89-square-meter apartment at the time of the blaze. Authorities said the misuse of a liquefied gas cylinder might have caused the fire.
gaochangxin@chinadaily.com.cn
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