Last weekend’s police-state clampdown in Brisbane for the G20 summit was accompanied by two violent police attacks in the city’s working class suburbs, underscoring the atmosphere of intimidation surrounding the unprecedented security operation.

Last Saturday, while the centre of the Queensland state capital was virtually shut down by about 7,000 police, with 2,000 soldiers on standby, police were captured on video punching and pinning down a young disabled man in a suburban shopping centre, sparking outrage by horrified onlookers and going viral on social media.

Two nights later, just after the G20 lockdown was lifted, police shot and killed an apparently distressed young man after barging into his home—the third such shooting within two months—triggering dismayed condemnations by his mother and friends.

Both incidents were brutal displays of force. On Saturday afternoon, police kept attacking a 20-year-old man with half his legs missing and an 18-year-old woman at the Sunnybank shopping plaza despite calls by a crowd of shoppers to stop the assault. Footage of the violence was later uploaded to Facebook, where it received at least half a million views, with hundreds of people condemning the police.

In the five-minute video, two officers are seen wrestling the man, whose prosthetics legs have come off. The man is put in a headlock, and two officers try to handcuff him, at which point one is seen punching him four times. “Get off me,” the man repeatedly yells. The young woman is also pinned on the ground. After being hauled to her feet by her handcuffed wrists, she yells: “We haven’t even done anything wrong. I care for him, he’s disabled. Get off me, get off me.”

Madison Noble, who witnessed the incident and can be heard in the video screaming, “Oh my God, what the hell?” later told 9NEWS she was in tears and still found it hard to watch the video.

Declan Liu, who filmed the attack and posted it online, told the Brisbane Courier-Mail: “They got him in a UFC lock on the ground and they started pounding on him. The thing I really hated about it was when the two other cops come through and they started yanking him. In real life it looked a lot worse … people were shocked, no one wanted to step in or anything, but there was a big crowd.”

In a bid to turn popular opinion against the two young people, a police spokeswoman told the Courier-Mail they had stolen a carton of 12 bottles of wine, implying this was a serious offence. While the police officially declined to comment on the public complaints of the violence used, Queensland Police Union president Ian Leavers immediately supported the police action. Without offering any evidence, let alone waiting for the outcome of any inquiry, he accused the pair of acting up for the cameras.

Sunnybank is one of a swathe of suburbs across southern Brisbane that are dominated by mass unemployment—with official jobless rates of around 20 percent and much higher for youth. The impact of decades of industrial closures is now being compounded by a sharp downturn in Queensland’s mining industry, which is impacting on engineering, equipment and other related industries.

In the early hours of Tuesday morning, police killed Laval Zimmer, 33, inside his home at Kippa-Ring, another working class suburb with high unemployment on Brisbane’s northern outskirts. According to the police, officers went to the house after hoax 000 emergency calls and were forced to fatally shoot Zimmer after he lunged at them with a knife.

It later emerged that Zimmer, an apprentice auto mechanic who suffered epilepsy and schizophrenia, was in a disturbed state after being tasered and arrested by police on Monday afternoon during an incident at a local petrol station. Stuart Duce, who lived with Zimmer, told reporters: “He was really upset with the police that afternoon. He tried to call them to protest about what had happened.”

Another of Zimmer’s roommates, Adam Sant, said he was “devastated” by the shooting. He told Fairfax Radio 4BC that police officers had woken him up just before one am, asking to see Zimmer. When Zimmer then appeared and rushed at the police, Sant said he tried to intervene, but was peppered-sprayed by the police. “I’ve dropped to the ground and he’s gone to rush them so they have shot two bullets and actually hit him in the chest.”

Zimmer’s mother told the Courier-Mail that people knew her son as a peaceful and generous individual, not a violent man. “Laval was not the type to walk with a knife. He must have been feeling threatened or scared,” she said. “I don’t understand why they couldn’t shoot him in the leg and not the chest ... I feel so sad. It should not have happened this way.”

Friends and neighbours, who placed wreaths at the house or floated them out to sea, were visibly traumatised. Several condemned the lack of adequate mental health services in the area. Once again, however, Queensland Police Union president Leavers defended the police response, saying that while officers “will always show great restraint,” they were “entitled to go home at the end of their shift to their families.”

Police across Australia have killed other mentally-ill people in similar circumstances in recent years—evidence of a shoot to kill mentality being inculcated in police amid conditions of glaring inequality, social distress and deteriorating mental and other public health services.

Zimmer’s shooting was the third involving police in working class areas of Brisbane since late September, when a paramilitary unit besieged and killed a 42-year-old former oil rig worker in a hail of automatic gunfire in Inala, horrifying local residents. Last month, police shot a man in the head and arms while investigating a theft of a trailer and mower at Rochedale, but the man survived.

These police shootings are occurring in an atmosphere of heightened fear and police mobilization, fuelled by the federal government’s decision to raise the official “terrorism alert” level on September 12, followed by Australia’s largest-ever police and intelligence agency “counter-terrorism” raids on September 18.

The federal and state governments, and the security forces, then used the G20 summit as a testing ground for measures such as saturation policing, cordoned-off zones, police-military checkpoints, rooftop snipers and draconian police powers.

The latest two police attacks in Brisbane are another demonstration of the preparations being made to deal with social unrest and opposition to the agenda of war and austerity being pursued by the corporate elite.