From afar the dead fish look like a white ribbon on the water of Haihe River, which is about four miles away from the blast center, but the corpses of the 2-inch-long fish smell very bad, local residents said.
The warehouse where the explosions occurred stored as many as 40 different chemicals, including massive amounts of highly toxic sodium cyanide, according to state press agency Xinhua.
In response to the photos, people on Chinese social media have questioned whether chemical materials leaked and contaminated the environment. However, according to CCTV, the results of an official investigation show that no cyanide has been detected.
Officials said in a press conference broadcast by CCTV News Thursday morning that there could be different reasons the fish are dying and that possible contaminated water has been kept within the area.
But officials have been losing credibility in handling the investigation because internet censors have been deleting posts from the popular Chinese social media site Weibo in order to control information.
In response to the die-off, people on Chinese social media have been making sarcastic jokes, speculating that the fish died from "drowning" because they were "suicidal for being alone on the day of Qixi."*
But according to CCTV, officials basically asked people to chill out. "Tianjin's water environment has always been problematic," said Deng Xiaowen, the director of Tianjin Environment Monitoring Center.
Beimeng Fu is a BuzzFeed News World Reporter covering China and is based in New York.