Chinese state censors have been busy over the weekend scrubbing the web clean of damning posts about the Tianjin explosion.

Apart from the sites the government confirmed it shut down for "spreading rumours" about the explosion, posts on Chinese microblog Weibo have also been disappearing.

See also: Tianjin explosion site evacuated after new blasts as families demand answers

Some of the recent posts that have been deleted now appear on Freeweibo.com, a site that captures deleted Weibo posts.

One user wrote those in charge have the responsibility to conduct a thorough investigation into the cause of the explosions, and additional third party experts should be brought in or the firefighters would have died in vain. He also remarked on the apparent "calmness" of the Tianjin authorities at the press conference amid the drama unfolding outside the room.

Another asked why such dangerous materials were within just 600 metres of a residential complex.

One of the most retweeted posts over the weekend, which has now been deleted, is of a report from the Southern Weekly (Nanfang Zhoumo) newspaper citing a firefighter who said rescuers didn't know they couldn't use water to douse the flames. The post said that after the firefighters spent 10 minutes hosing the flames, they heard crackling noises as the white crystalline sodium cyanide reignited. The link to the article on the newspaper's website now returns an error message, as well.

Reporters and families outside a press conference about the Tianjin explosion Image: Weibo

There are several posts from Chinese publication The Paper (Pengpai Xinwen) that have been deleted. One described the emotional scene outside the press conference where the families of the fallen firefighters were crying, and noted that some families were blocked from entering the room.

Another post by The Paper that has been deleted cited the Beijing News saying that toxic sodium cyanide from the blast site has leaked into the ditches.

Hong Kong-based George Chen, a managing editor with the South China Morning Post (SCMP), tweeted over the weekend about the censorship: