Applications for key workers to have coronavirus tests have reopened - a day after they closed due to high demand - but many of the available slots and home kits ran out within minutes.
The huge demand for tests follows a dramatic expansion of eligibility to all key workers who have symptoms and members of their household, after them previously only being open to health workers and emergency services.
The government says it will stagger the available tests and appointments, so more may become available later in the day.
On Friday, when applications for tests first opened, some 5,000 home tests were ordered within two minutes of being made available.
And 15,000 drive-thru test appointments were booked within an hour.
With more than one million NHS and hundreds of thousands more 'key workers' in the UK, it's no surprise tests are heavily sought after.
It's estimated 10.72 million people with their families are no eligible for tests.
As of 8.50am Saturday morning all available home test kits, drive-thru appointments in England, Wales and Northern Ireland had gone.
The only appointments available to book at the moment are those in Scotland.
The Department of Health (DoH) has said it is working to "rapidly increase availability".
The government hopes to have 18,000 daily home testing kits available for key workers by the “end of next week”.
The expansion of eligibility is part of the government's drive to test carry out 100,000 coronavirus tests a day by the end of April - as of Friday, capacity was 51,000 and there were 28,000 tests done.
People can register for a test at www.gov.uk/coronavirus.
When the website is up and running, after registering, people will receive a text or email with an appointment at a drive-through centre or can request a home test kit, although the latter are in limited supply.
A help desk has been established to aid the process, while mobile units run by the Army are travelling around the country to where they are needed, such as care homes.
Test results from the drive-through sites will be sent out by text within 48 hours, and within 72 hours of collection of the home delivery tests.