The association overseeing Chinese journalists issued a rare statement of protest after reporters were blocked by local residents and security guards while trying to report on the aftermath of a blast outside Beijing.

A powerful explosion on Wednesday morning suspected to have been triggered by a gas leak at a fried chicken shop in Sanhe, a city in Hebei province adjacent to Beijing, ripped off the facade of nearby buildings, killed seven people and injured 27 others.

As reporters arrived at the scene, including from state-run radio and television as well as foreign journalists based in Beijing, some were verbally challenged by crowds and physically prevented from conducting interviews or filming.

A video clip on Chinese social media showed two men in black uniforms blocking the camera of a reporter from state television CCTV as she attempted to conduct a live interview. Another showed a reporter from China's state radio saying she was being pushed about by more than a dozen people.

News is highly controlled in China due to concerns of social stability and national security, but it is unusual for state journalists to be prevented from reporting in public.

Local governments should support reporters in their work after a major emergency incident, the All-China Journalists Association (ACJA), overseen by China's Communist Party, said in a statement on Wednesday following the Sanhe explosion.

"They must not obstruct the normal duties of reporters in a simple and rough manner just to control public opinion," ACJA said in a rare defence of reporters' right to report.

The treatment of journalists belonging to state-run broadcasters at the Sanhe blast prompted concerned posts on Weibo, China's popular but heavily censored messaging platform.

"Even CCTV reporters were subjected to this, let alone other media," wrote one Weibo user. "If mouths are covered during a prominent public safety incident such as this, what can be said of other public incidents?"

Sanhe's government, in a statement on Thursday, apologised for the "poor communication skills" of front-line staff as they tried to persuade reporters to leave due to the risk of another gas leak.

"We are deeply aware that safeguarding the legitimate reporting of journalists is needed to satisfy the public's right to know," the statement said.

Foreign reporters are sometimes harassed, including physically, by ordinary citizens who say foreign journalists are out to smear China's image.

In 2021, some foreign journalists complained of being harassed and threatened by civilians while covering floods in central China, prompting the International Federation of Journalists to urge authorities to ensure journalists can report safely and independently.

China's government says it welcomes foreign media to report on China provided they followed the law.