Among the beachgoers was Greensbrorough couple Rachel and Bonny Nardella who visited to Chelsea with their two young sons, as they often do on sweltering summer days.
But the recent attacks had left them fearful of staying at the beach into the early evening.
“I would definitely rethink staying here or coming here later in the day now,” Ms Nardella said. “For this to happen in Chelsea, I can’t believe it. It’s just really sad.”
Heathmont local Jacinta Collier said news of the assaults had left her feeling scared.
“I would really rethink the time of day I come [to the beach] from now on,” she said.
Some Chelsea traders also feared violence along the foreshore could worsen and said it was already affecting business.
“People are scared,” said Teresa Wang who owns the Chelsea Pricecut gift store. “But there is definitely a risk for our business because fewer people will come to the beach because they think it’s dangerous. I would try and avoid the beach at night-time. It’s actually quite scary.”
But local cafe owner Tina Sidaloi said the increase in police presence on the foreshore was “over the top”.
Ms Sidaloi, who owns the Bubbly Beans Cafe on Nepean Highway, said it was instilling a sense of fear in the community and inciting racism rather than solving the problem.
She said some African youths who had come to her cafe after spending the day at Chelsea beach had spoken of being racially vilified by other beachgoers.
“They come to the shop and they say people have told them they’re not welcome at the beach because of the colour of their skin,” she said.
“These are young people who haven’t robbed or hurt anyone. They’re just going to the beach like anyone else. What happened [on Thursday night] is awful and it should not happen anywhere, ever. I’m Lebanese. I’m sure in my culture there are bad people too, as there are in every culture, but we shouldn’t be taking it out on people who haven’t done anything wrong just because they’re the same nationality.”
Ms Sidaloi believed the root of all the trouble on the foreshore was young people drinking and taking drugs, despite an alcohol ban in the area.
“There are people drinking illegally there all the time,” she said. “If police focused on making sure that wasn’t happening, I think it would help the situation.”
The trouble began about 6pm on Thursday with an altercation between two groups after an argument about jetskis, with riot police later storming the foreshore.
Later on Thursday, it is believed that another group of youths were involved in three incidents on the beach between 9.30pm and 10.30pm.
A male swimmer who spotted the thieves rummaging through his belongings was assaulted when he confronted the group before the youths fled with mobile phones and wallets, police said.
The group then approached another three men and assaulted them. One of the victims, a 28-year-old man, also had his phone stolen.
A 19-year-old man who was sitting on the beach and was then glassed in the head with a beer bottle by the group. He was taken to hospital where he received stitches.
The offenders are described as being of African appearance and aged in their late teens or early 20s.
Superintendent Sharon McKinnon said the attacks were unprovoked and police numbers in Chelsea would be doubled on Friday night.
“We will be working even harder to ensure it doesn’t [happen again] because we don’t want people not going to the beach … it’s one of the most important parts of the wonderful culture we have in this country,” she said.
She also reassured beachgoers that Chelsea would be safe on New Year’s Eve with a beefed-up police presence.
There are fears that the violence at Chelsea is a result of a police crackdown at St Kilda beach with offenders simply moving down the bay to their next coastal target.
Earlier this month, footage emerged of the moment two men were ambushed and bashed unconscious in an “unprovoked, random, senseless and brutal” attack by a group of 20 youths on the St Kilda foreshore.
But Police Minister Lisa Neville said the crackdown at St Kilda beach, which led to more than 30 arrests over the past six weeks, had not pushed crime to other beaches.
“Our beaches are safe right across Victoria and we have police at every single one of them,” she said.
She added additional police had been deployed at other seaside locations. “It doesn’t matter whether you’re at St Kilda, Chelsea or Frankston,” she said.
“They have people everywhere – undercover as well as uniformed members backed up by specialist public order response teams.”
Speaking at St Kilda Beach on Friday morning, Ms Neville said crime prevention efforts in the area over the past month such as new CCTV cameras, extra police, as well as alcohol and glass bans, had made the foreshore safer. “What we have seen is families come back and embrace this area,” she said.
Investigators are urging anyone with video footage of the Chelsea incidents to contact police.
Melissa Cunningham reports breaking news for The Age.
Craig Butt joined The Age in 2011 and specialises in data-driven journalism. In addition, he helms the popular Melbourne Express blog on Thursdays and Fridays.