Three hundred soldiers recalled to a barracks in Aldershot this week have complained they are being locked down without sufficient hygiene essentials amid concerns that their cramped conditions could lead to a coronavirus outbreak.

Troops from the 1st Battalion Grenadier Guards said they had been asked to self-isolate with their families but then hauled back to an environment that had not been supplied with any personal hand sanitiser or other cleaning equipment.

The lockdown means soldiers have been unable to shop outside to obtain personal supplies, while people within the camp in Hampshire who are showing coronavirus symptoms have been offered no medical treatment or support, according to those in the unit.

Although thousands of troops have been placed on standby to help tackle the coronavirus crisis, frustrated soldiers in Aldershot said it was not clear why they had been recalled to “essentially an open prison”.

“They’ve taken hundreds of people away from their families and their safe environments, only to thrust them in with hundreds of other people who are potential carriers, unbeknownst to themselves,” according to a member of the unit who contacted the Guardian and asked not to be named.

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“We even have a dozen or so people within camp who are self-isolating through showing symptoms, and no effort is being made for them to receive medical treatment at all. They’re just being told to stay in their rooms and if they have to smoke they’re to smoke out of their window.”

This week it emerged that 2,000 troops had been placed on 24 hours’ notice to assist the health service or meet any other emergency request. A further 1,500 have been placed at 48 hours’ readiness.

But concerns are growing in some quarters of the armed forces that the military is not practising physical distancing and could be at risk of spreading coronavirus when it is most needed, while images are circulating on social media of forces personnel conducting physical training in large groups.

Leaked emails show commanding officers are treating each company as a single household unit for coronavirus purposes, and while efforts are made to respect the suggested two-metre physical distancing standard it is conceded that in training that cannot always be the case.

Quick guide UK lockdown: what are the coronavirus restrictions? Show Hide What do the restrictions involve? People in the UK will only be allowed to leave their home for the following purposes: Shopping for basic necessities, as infrequently as possible

One form of exercise a day – for example a run, walk, or cycle – alone or with members of your household

Any medical need, to provide care or to help a vulnerable person

Travelling to and from work, but only where this is absolutely necessary and cannot be done from home Police will have the powers to enforce the rules, including through fines and dispersing gatherings. To ensure compliance with the instruction to stay at home, the government will: Close all shops selling non-essential goods, including clothing and electronic stores and other premises including libraries, playgrounds and outdoor gyms, and places of worship

Stop all gatherings of more than two people in public – excluding people you live with

Stop all social events, including weddings, baptisms and other ceremonies, but excluding funerals Parks will remain open for exercise, but gatherings will be dispersed.

An email from a commanding officer in the Royal Engineers seen by the Guardian says: “Where we can respect social distancing in the training environment we should seek to do so.” But it adds: “This will not always be possible, pleased [sic] be relaxed about this.”

It says soldiers should be particularly careful if the public are watching them train on an exercise ground or elsewhere. “Conscious that out on the area we are subject to the scrutiny of the general public where we must be perceived to be adhering to social distancing as much as possible.”

Ministry of Defence sources argue the army is one of several unique public sector environments, which like the health service and police have at times to operate in groups. But they insist physical distancing and other Public Health England coronavirus guidelines are being observed where possible.

Soldiers in the Grenadier Guards have single-person rooms, the army source added, and special arrangements such as staggered mealtimes had been arranged to help distance people while they are on standby at barracks. “Soldiers are used to keeping good hygiene: there are rigorous hand-washing routines for instance,” the source said.

But the concern among the Grenadier Guards is that whatever the intention, in practice troops are cramped when they could have been kept safely at home – and that creates unique risks as the highly contagious coronavirus spreads.

The Grenadier Guards soldier who contacted the Guardian described the eating arrangements and accommodation situation in Aldershot as laughable. “Surely the safer option would be for people to just stay at home, that way minimising the risk of infection, instead of sharing tables, cups, plates and cutlery with 300 others?”

It was impossible in practice to minimise contact with “people living in what are essentially university-style dormitories that have a shared kitchen and shared washing machines and dryers which obviously present considerable risk of cross-contamination. No cleaning equipment has been provided such as hand sanitisers for personal use, so people are having to share their own limited stock.”

The soldier said he hoped senior officers would have a rethink. “Surely in the midst of a recruitment and retention nightmare for the army, this is absolutely the last image we should be portraying to the public? Especially if sometime soon we are to be heralded as saviours for deploying to help stop the spread of this virus, if the very soldiers on duty cannot be trusted to buy their own toilet roll from the shop?”

An MoD spokesperson said: “We are well prepared for the outbreak of coronavirus, and have well-rehearsed plans in place for dealing with health matters. All our people have been reminded of the guidance issued by Public Health England, which is the same advice for the general population.”