Officials in the Chinese port city of Tianjin agreed on Wednesday to negotiate with angry residents left homeless by massive explosions, after a series of protests seeking compensation for their destroyed homes.

China keeps a tight grip on shows of public dissent, requiring public gatherings to have permission and using police to round up protesters, though officials sometimes meet with disgruntled citizens to defuse tensions.

About 150 demonstrators who lost homes in the city's Binhai New Area where the blasts occurred a week ago were caught by surprise on Wednesday, after several officials spoke to them following a press conference by Tianjin mayor Huang Xingguo and others at a luxury hotel.

For days, protesters -- under the watchful eyes of police -- have been shouting slogans and demanding compensation for their damaged apartments, some just hundreds of metres from the site of the blasts that left at least 114 people dead and hundreds injured.

They have also demanded a meeting with officials to press claims that the government should pay for new apartments.

Several officials emerged after the press conference and approached the demonstration, causing a chaotic scene of screaming and jostling as protesters rushed toward them, as Chinese and foreign journalists recorded the event.

"Buy back!" they shouted repeatedly -- voicing their demand for new homes -- as officials, including Zong Guoying, the Communist Party secretary for the district, took megaphones to speak.

Officials said they understood the plight of the residents and were concerned about their health.

One proposed that protesters from each affected apartment complex select representatives for talks with district officials.

There were intermittent bursts of anger in response to remarks by the officials, but gradually representatives for some of the apartments were agreed.

But protester Xuan Hong stressed that all the officials had really done was commit to talks.

"Positive, but still no solution," he told AFP.

"I think they already have their solution but I'm not sure they can meet our expectations," he added, referring to the demand to purchase new homes.

- 'Chinese democracy' -

Indeed, regarding that, Zong said that it was just one option.

"We have many, many ways", he told AFP amid the scrum as other officials addressed the protest, suggesting that the government, the apartment developers and the owners need to sit down as "partners".

Asked if officials had come out in response to the protests, he said: "This is our responsibility. We are the people's government."

Pressed as to why Huang did not meet them, Zong said that was his responsibility not the mayor's.

"He is in charge of the whole city," Zong said. "I'm in charge of the Binhai New Area."

At the press conference Huang said: "I have leadership responsibility that cannot be shirked."

Premier Li Keqiang visited Tianjin on Sunday to inspect the area, though some online commentators questioned why he took four days to do so.

The scene outside the hotel unfolded as skies cleared in Tianjin. Rain had fallen in the morning and on Tuesday, further raising fears over damage to the environment from the residue of poisonous chemicals.

Around 700 tonnes of highly toxic sodium cyanide were at the site, officials have said, and water could spread it more widely.

Despite the loud demands for compensation, the protesters have also taken some pains to avoid angering officials, unfurling banners stressing that they "love the party" and "trust the government" as well as making sure to show respect for those who lost their lives in the disaster.

"Chinese democracy is different," Zong, the Communist Party secretary, said of Wednesday's scene. "But the Chinese government is working for the Chinese people."

China blast warehouse owners hid stakes in firm: Xinhua
Beijing (AFP) Aug 19, 2015 - The owners of a Chinese hazardous goods storage facility at the centre of giant explosions -- including the son of a former police chief -- hid their stakes in the firm through friends, state media reported Wednesday.

Ten executives from Tianjin Rui Hai International were detained after last week's blasts in the northern port of Tianjin, which triggered a giant fireball and killed at least 114 people.

The blasts sparked fears of toxic pollutants in the city's air and water, though authorities have insisted both are safe. Around 700 tonnes of highly poisonous sodium cyanide were at the site, officials have said.

The official Xinhua news agency was given access to some of the suspects and quoted them extensively, as authorities try to pin blame for the disaster on local officials and individuals and head off wider criticism of China's one-party state.

Dong Shexuan, 34, the son of the port's former police chief, owned 45 percent of Rui Hai through a schoolmate, Xinhua reported. The rest was owned by Yu Xuewei, a former executive at state-owned chemical company Sinochem, but held in the name of a friend of his, it said.

"I had my schoolmate hold shares for me because of my father," the official agency quoted Dong as saying. "If the news of me investing in a business leaked, it could have brought bad influence."

The head of a government team investigating the blast on Wednesday vowed to find the individuals and companies responsible.

"No matter who, no matter what background they have, it must be investigated clearly," Yang Huanning, executive vice minister of public security, told state television.

Dong used his connections in the police and fire departments to help the company obtain the necessary permits and pass inspections, Xinhua said.

"My connections are in police and fire. When we needed a fire inspection, I went to meet with officials at the Tianjin port fire squad. I gave them the files and soon they gave me the appraisal," Dong said, according to Xinhua.

Tianjin Rui Hai International Logistics operated without a licence for nine months to June, Xinhua reported.

"After the first licence expired, we applied for an extension," it quoted Yu as saying. "We did not cease operation because we did not think it was a problem. Many other companies have continued working without a licence."

Sinochem has two hazardous chemical warehouses near the site of last week's blast, according to Greenpeace. It said both violated Chinese law requiring such facilities to be at least 1,000 metres from public buildings, major roads and residential units.

The Rui Hai warehouse violated the rule, state-run media previously reported, and Xinhua said Wednesday there were housing blocks and a train station within 650 metres of it.

Dong and his partners found an appraisal company that ignored the facts, the news agency said.

Tianjin Mayor Huang Xingguo on Wednesday took responsibility for the accident on his watch.

"I have leadership responsibility that cannot be shirked," he told a news conference.

A corruption investigation into the head of China's work safety watchdog has also been announced in the wake of the blasts.