Trafalgar Square at night is silent and almost empty, the usual crowds of noisy tourists visiting London replaced by clusters of homeless people, who wait on the steps of the National Gallery for food to be distributed. But these are not all long-term rough sleepers: central London is seeing a surge of newly unemployed restaurant and pub workers forced to sleep on the streets because they can no longer afford to pay rent.

Rough sleepers like Martin, a recently-sacked chef from Poland, are finding life under lockdown increasingly difficult and dangerous. “London has become so strange and sad. The only people who are out look like they are looking for drugs. There are a lot of crazy people with knives,” he said.

The government says it has housed 90% of those who were sleeping rough nationally by paying for hotel rooms, in an unprecedented drive over the past month to stop the spread of Covid-19, with 5,400 housed including 1,800 in 10 hotels across London. But in the capital, hundreds of tents and cardboard box encampments remain and conditions are getting much harsher for those still – or newly – on the streets.

The city’s day centres have been closed to prevent the transmission of the virus, leaving the homeless with no place to shower or wash their clothes, no toilets and nowhere to access regular food supplies.

The disappearance of commuters means that no one is offering money to the destitute, at a time when most soup kitchens and food banks are not operating, and when the closure of cafes has meant the homeless no longer receive unsold sandwiches at the end of the day. It has been left to a few small groups of volunteers to provide thousands of meals a week.

Lalji Kanbi: ‘The hotels are a lottery, if you win, you win. I’ve given them my details twice.’ Photograph: Sean Smith/The Guardian

Although a minority of those who remain sleeping rough are there by choice and have rejected offers of hotel rooms, most of the newly homeless are still hoping for help, and feeling very vulnerable in the deserted backstreets of central London at night.

Martin, 27, worked his way up through London’s kitchens, starting as a porter when he arrived in the UK eight years ago to his most recent job as chef de partie at a fashionable restaurant in east London. He was abruptly sacked shortly before the lockdown began, and had to leave the room he was renting because he had no savings. He has been sleeping on a bit of pavement near Charing Cross station for six weeks.

He said he has been told five or six times by outreach workers that someone will call him to organise a room in a hotel. “I waited for a call. I’m still waiting. Maybe the hotels are full,” he said. In the last couple of days his phone battery has in any case gone dead, and with cafes closed there is nowhere to charge it. He finds sleeping on the street unsafe and alarming.

Brian Whiting, a volunteer with the organisation Under One Sky, which started nightly food deliveries at the end of March, said he was disturbed by the number of newly homeless ex-hotel and restaurant staff. “One of the really distressing new things is the hospitality homeless. We’re seeing so many people who were working in kitchens, hotels and pubs until a few weeks ago. They’re so obviously ill-equipped to be out there. The long-term rough sleepers know how it works, but for them it’s very new. They look shell-shocked.”

“I’m still hanging on to my sanity, just,” a man from South Africa, who had been working for five years as a waiter in London, said from the office doorstep where he has slept for the past three weeks since losing his job. He laughed when the volunteer asked him if he was eligible for furlough payments, and said the job came through an agency, and there had been no mention of financial support. Most of those pushed into homelessness had insecure jobs and precarious living arrangements, and no ability to navigate the benefits system or wait for payments.

The charity Under One Sky provides food for rough sleepers, cooked by the Punjab restaurant in Covent Garden. Photograph: Sean Smith/The Guardian

On the other side of the street, Whiting was dismayed to see Katarina, 34, a recently-sacked waitress from Italy, preparing to sleep again in the doorway of a cocktail bar. “It’s nice to see you, but I wish you weren’t here,” he said, giving food to her. He was concerned about her deteriorating mental health, and suspected she had started taking class A drugs. He has reported her to Streetlink, a charity that connects rough sleepers to support services, a few times, but she remains in the same spot. “She wants to be helped. I don’t understand why she hasn’t been picked up.”

Aside from the practical difficulties, everyone remarks on the disconcerting silence of the capital.

All the normal sounds and smells are absent – the salty, greasy smells from fast food restaurants, the wafts of coffee from snack bars, stale beer odours rising up from sticky pavements, the stench of rotting food seeping out from kitchen dustbins, even the trails of diesel fumes, have all gone.

There is no noise of people laughing or shouting, no one bellowing into their mobile phones, no sounds of plates clattering at pavement cafes. Bins are not overflowing with coffee cups and discarded newspapers. Even the pigeons seem hungrier, rushing to peck at food parcels placed on the pavement by volunteers, who are instructed to not to hand them to people in order to maintain a 2-metre distance. A woman picking up cigarette butts has to search harder to find anything worth collecting.

Amrit Maan, the owner of the Punjab restaurant in Covent Garden, who has kept his kitchens open to cook around 2,500 meals a week for Under One Sky and a Sikh charity, Nishkam Swat, to distribute, said he was troubled by the emptiness. “You can hear the wind rushing through the streets. It feels so eerie, like waking up in a post-apocalypse movie.”

Food is cooked at the Punjab restaurant, Covent Garden, for homeless people in London. Photograph: Sean Smith/The Guardian

A welder from Poland, sleeping in the park behind the Savoy, declined food but wanted information about where he could wash; he said he had been unable to have a shower for the past five weeks since arriving in London speculatively to look for work. Whiting left food for a man asleep beneath the stucco columns of the Lyceum Theatre, where the Lion King is no longer showing. “There’s some human excrement. I’m sorry to point it out, but it’s inevitable. Everything is closed,” he said.

Alexander, from Romania, who worked as a cleaner and caretaker at a pizza chain until he says he was sacked just before the lockdown, was more experienced at sleeping rough in central London, since he was already unable to afford to rent a room on his minimum wage earnings even when he was in work, and has been living on the streets near Leicester Square for 18 months.

But finding enough cardboard to build himself a sheltered space to sleep in has become much more problematic since all the businesses closed down and stopped throwing away packaging. He spent the past few weeks recording thousands of videos on his phone of deserted London streets, from different vantage points, and posting them on Twitter – providing fascinating pavement-level footage of a city in lockdown – until his phone was stolen.

Adrian Potcki, 24, from Poland, also had his phone stolen while he slept in a restaurant doorway, in St Martin’s Lane, next to the now-empty Coliseum. He was working as a night cleaner for a bank, an agency job, before being sacked when lockdown was announced. He found himself unable to continue paying for his room in a flatshare in north London. “I think the bank closed, and didn’t need cleaning,” he said, but he is unsure, because the agency simply told him the job was over. “I couldn’t pay the rent for my room. I tried to ask the landlord to give me time, but I couldn’t work it out with him,” he said. He was finding his first exposure to homelessness very difficult. “It’s a really tough time. I don’t feel safe.”

He, like most of the other recently-unemployed new rough sleepers interviewed, said he did not want to have his photograph taken. “I don’t want to become a famous person because I’m homeless. This is something I would like to forget,” he said.

Mikkel Juel Iversen founded Under One Sky. Photograph: Sean Smith/The Guardian

Previously Under One Sky has only organised food handouts in the winter, but began providing food for rough sleepers when it became clear that lockdown was causing unprecedented difficulties. “In the eight years since we have been serving this community, we have never witnessed a more distressing situation for those sleeping rough in London than the one unfolding right now,” said Mikkel Juel Iversen, who set up the organisation in 2012.

“Two days after lockdown we went out on the streets to see what the situation was like and we met people who hadn’t eaten for days. There are now large parts of central London where the only people you see are homeless people, drug dealers and police. There is a growing sense of desperation. We have been ramping up numbers every week.”

The newly-homeless also include people like Robin Clark, released last week from prison, and still trying to get his life together. “I can look after myself but it is hard with no showers or toilets.” Lalji Kanbi has been homeless for a while, and is hoping for a hotel room. “The hotels – it’s like a lottery, if you win, you win. I’ve given them my details twice.”

Within the rough sleeper populations there are hierarchies of destitution. There are those like Colin Reynolds, 47, currently sleeping in a tent near the Thames because he was unable to live with his parents during lockdown, who feel they are just about coping. But there are others who look close to death.

About 10 people are sheltering beneath a scaffolded shop front near Charing Cross station (where the underpasses that used to shelter dozens of homeless have been closed off); volunteers said most had long-term drug and alcohol problems. One man was lying in a foetal position on the cold pavement, passed out, watched over by his girlfriend. No one here was hungry, but they accepted water and biscuits for their dogs.

Tom Copley, London’s deputy mayor for housing, acknowledged that there was more work to be done, noting that a count last week had registered 498 people still sleeping rough. “It’s possible that the actual number will be larger, but we’ve been working at this as fast as we can; we’re trying to get more people in every day.” But he remained optimistic that the government drive to get most rough sleepers in for the duration of the lockdown could have positive long-term consequences. “We could transform the way we deal with rough sleeping and homelessness to make sure that the issue is dealt with in the long term,” he said.

There is caution from others involved in the process. “There is no clear exit strategy from central government. Some councils are working to make sure that no one is returned to the streets, but that is very difficult to sustain unless there is a commitment to funding because the cost of that is so beyond what’s available from central government,” one official, working on the national drive to house rough sleepers centrally, said.

Jason Moyer-Lee, the general secretary of the Independent Workers of Great Britain Union, which represents agency staff, said more needed to be done for people made homeless after being sacked. “Low-paid service sector jobs, with zero-hour contracts and agency workers, were extremely precarious before this situation, and the fact that, despite the government schemes, some people are being driven into homelessness demonstrates the inadequacy of these schemes. This needs to be sorted now.”

• This article was amended on 28 April 2020 because an earlier version incorrectly referred to Amrit Maan as the manager of the Punjab restaurant in Covent Garden. He is the owner.