Parts of England and Scotland are now subject to ''local lockdowns'' to help stop the spread of Covid-19.
In Aberdeen, pubs and restaurants have been told to close and people asked not to visit others' houses, after a cluster of coronavirus cases.
It happened after separate households were banned from meeting up indoors in Greater Manchester, where a major incident was declared following a rise in cases.
Similar restrictions apply in east Lancashire and parts of West Yorkshire.
What measures are being taken?
In Aberdeen, a ''significant outbreak'' of 54 coronavirus cases prompted lockdown measures to be reintroduced. Pubs and restaurants will be closed, and people are being told not to travel to the city, while residents should not travel more than five miles for leisure purposes.
Residents there and in other locked-down areas are not allowed to socialise with other households in their homes, gardens or any other indoor venue, either inside or outside the local area. Travelling for work or education is allowed, but other travel is not advised.
The restrictions will be reviewed next Wednesday, and may be extended further if necessary.
Covid-19 cases in NHS Grampian
Confirmed cases over last 30 days
Local lockdown rules vary from place to place.
In the parts of England under lockdown, people can still visit pubs, restaurants and other hospitality venues, but only with members of their household.
They can also meet up to six people from different households in an outdoor public place.
The government is passing new laws to enforce these rules, and police will be able to ask people to disperse, and to issue fines.
In Blackburn with Darwen, indoor gyms, swimming pools and other sports facilities must remain closed.
While shielding has now been paused in most parts of England, those shielding in local lockdown areas should continue to do so. Shielding in Charnwood and Blaby in Leicestershire, and also in Luton in Bedfordshire will continue until 17 August, while shielding guidance in the other affected areas will be under review.
What has Leicester's local lockdown involved?
The UK's first local lockdown was in Leicester, after infections rose there at the beginning of July.
Non-essential shops were told to close, while bars and restaurants couldn't reopen with the rest of England.
Most venues can now open but leisure centres, gyms and pools must remain closed.
The borough of Oadby and Wigston on the city's outskirts has also come out of local lockdown, although shielding still applies there.
Why have the latest restrictions happened?
Local clusters or outbreaks are being targeted to stop the spread as quickly as possible and prevent a national lockdown.
A cluster is a group of cases in one place like a hospital, factory or school. When clusters are linked, this is called an outbreak.
Data showing the number of cases in a particular place is used to help decide what action should be taken.
Cases are also identified through testing, with mobile units and door-to-door testing often taken to at-risk places.
Public Health England has also produced a watchlist of areas, based on new coronavirus infection rates, and other local intelligence.
Why are there local lockdowns?
Local authorities and central government have been given new powers to stop specific outbreaks of Covid-19.
These actions could range from targeting a hospital or factory, to locking down a whole city.
Local authorities were given powers to:
- Close specific premises
- Shut outdoor spaces
- Cancel events
Ministers can:
- Close sectors or types of premises in local areas
- Introduce localised stay at home orders
- Reduce the maximum size of gatherings
- Restrict the use of transport
- Stop people leaving a certain area
Can police enforce a lockdown?
Police have powers to enforce a local lockdown. For example, if they believe that somebody is staying away overnight, they can tell them to return home.
They can also fine people for breaking the rules, and may issue a "prohibition notice" directing somebody not to do something.
But if a resident from a locked-down area wanted to go to a bar in another part of the city, for example, there is nothing legally to stop them.
Instead, the government hopes people's sense of civic responsibility will see them follow guidance to stay at home.
What has been said about the rest of the UK?
A local lockdown was considered in Anglesey after an outbreak in June, Public Health Wales says, but it didn't happen.
In Northern Ireland, the government says that any potential clusters or outbreaks will be handled using "appropriate infection control" in line with its guidelines for handling any disease outbreak.