HONG KONG -- Protesters in Hong Kong threw gasoline bombs and police fired tear gas Saturday in renewed clashes over anti-government grievances.

Reporters saw at least one person arrested after violence erupted following an afternoon march by several thousand people in Tuen Mun, a district in the northwest of the Chinese territory.

Hong Kong is in the fourth month of sometimes violent protests that occur every weekend. They started with opposition to a proposed extradition law and have expanded to include demands for greater democracy.

Most protesters in Tuen Mun were peaceful but some threw gasoline bombs and bricks toward police who faced them down the street. They appeared to fall short of the police and there was no indication anyone was hit.

In the evening, protesters gathered at a shopping mall in another district, Yuen Long. Some threw gasoline bombs in the street. A government statement said some were thrown toward police vehicles, endangering the officers inside, but gave no indication anyone was injured.

In both areas, police with riot helmets and shields responded by firing tear gas.

Elsewhere, scuffles were reported as government supporters heeded a call by a pro-Beijing member of the Hong Kong legislature to tear down protest posters at subway stations.

The events are an embarrassment for China's Communist Party ahead of Oct. 1 celebrations of its 70th anniversary in power. Hong Kong's government has cancelled a fireworks display that day, citing concern for public safety.

The protesters in Tuen Mun marched about 2 kilometres (1 1/2 miles) from a playground to a government office building. Many were dressed in black and carried umbrellas, a symbol of their movement.

Protesters chanted, "Reclaim Hong Kong!" and "Revolution of our times!"

Most were peaceful but some took down a Chinese flag from a pole outside a government office and set fire to it. Protesters also set up barricades to block traffic.

A government statement said protesters caused unspecified damage to the Tuen Mun light rail station and threw objects onto the tracks.

An organizer quoted by government broadcaster RTHK criticized police for sending armed anti-riot officers.

That will "only escalate tension between protesters and police," the organizer, Michael Mo, was quoted as saying.

Hong Kong's leader, Chief Executive Carrie Lam, has agreed to withdraw the extradition bill. But protesters are pressing other demands, including an independent investigation of complaints about police violence during earlier demonstrations.

Protesters complain Beijing and Lam's government are eroding the "high degree of autonomy" and Western-style civil liberties promised to the former British colony when it was returned to China in 1997.

The protests have begun to weigh on Hong Kong's economy, which already was slowing due to cooling global consumer demand. The Hong Kong airport said passenger traffic fell in August. Business is off at hotels and retailers.

Police refused permission for Saturday's march but an appeal tribunal agreed to allow a two-hour event.

Protesters in Tuen Mun also complained about a group of women from mainland China who sing in a local park. Residents say they are too loud and accuse some of asking for money or engaging in prostitution.

Those complaints prompted a similar march in July, highlighting tension between Hong Kong residents and migrants from mainland China.

Later Saturday, protesters gathered at a mall in Yuen Long, where men with sticks beat protesters and subway passengers there on July 21 in an incident that caused controversy in Hong Kong.

Some protesters threw gasoline bombs on the street outside the Yoho Mall but there was no indication anyone was injured. Others started small fires in the street.

Also Saturday, there were brief scuffles as government supporters tore down protest posters at several subway stops, according to RTHK, the government broadcaster.

That campaign was initiated by a pro-Beijing member of Hong Kong's legislature, Junius Ho.

Near the subway station in the Tsuen Wan neighbourhood, a woman who was tearing down posters threw a bag at a reporter and a man shoved a cameraman, RTHK reported. It said there was pushing and shoving between the two sides at stations in Yuen Long and Lok Fu.

Ho made an appearance in the Shau Kei Wan neighbourhood but residents shouted at him and told him to leave, RTHK said.

Ho initially called for protest signs to be torn down in all 18 of Hong Kong's districts but he said Friday that would be reduced to clearing up trash from streets due to "safety concerns."

On Wednesday, the Hong Kong Jockey Club cancelled a horse race after some protesters suggested targeting the club because a horse owned by Ho was due to run.

Meanwhile, the Hong Kong airport announced restrictions on access Sunday following what it said were calls to disrupt traffic there.

The airport train from downtown will skip Kowloon and other stops en route, the Airport Authority said. Only passengers with valid tickets and travel documents will be allowed into the airport.