Speeding motorists have been travelling at more than double the limit during lockdown, UK police have revealed.
One driver was recorded at 134mph in a 40mph limit in London, while another was clocked at 115mph on a 40mph road in Greater Manchester.
A crash could put a "huge strain" on other blue light services, one force said, if it led to injury or staff being exposed to Covid-19 and forced into self-isolation.
Forces said the minority ignored rules.
It comes as Department for Transport data shows motor vehicle use in Great Britain has fallen by two thirds over the past month, particularly since the UK went into lockdown on 23 March.
Supt Julie Ellison, from Greater Manchester Police (GMP)'s specialist operations team, said: "My officers are working tirelessly to track down these offenders who are using the quieter roads as their own personal racetrack."
Police Scotland also said, over the Easter period between 10 and 14 April, 16 people were found committing drink or drug-driving offences.
"It is astonishing to see people behave so recklessly, particularly when we all need to be doing our bit to stay at home to protect the NHS and save lives," said Supt Simon Bradshaw, from Police Scotland's road policing division.
Recent incidents across the UK include:
- Seven people were killed in crashes in London since 20 March - including three motorbike riders and a cyclist
- Gloucestershire Police said two people had been killed in separate crashes. It also recorded one motorist at 74mph in a 30mph limit and another at speeds of up to 122mph on the M5
- GMP said it had caught more than 6,200 drivers breaking speed limits since lockdown began on 23 March. The force recorded a driver doing 115mph on a 40mph road and one reaching speeds of 129mph on the M62
- A man was recorded above 130mph on the A90 between Peterhead and Ellon, Aberdeenshire, on 12 April.
- A driver was stopped in Sudbury, Suffolk, travelling at 80mph in a 30mph limit with no insurance and no driving licence
- Police in Wales have seen speeds of 114mph in a 70mph limit on the A55 in Rhuallt Hill, another at 105mph in a 60mph limit on the A5 in Halton, Wrexham, and a third at 104mph in a 70mph limit on the A48 in Pensarn, Carmarthen
- Speeding has doubled on Lincolnshire's roads under the lockdown despite a reduction in the amount of traffic by two thirds, police said
- One driver was detected travelling at 112mph on the A2 Belfast to Bangor Road on 2 April, by the Police Service of Northern Ireland
"The concern we currently have relates to those undertaking unnecessary travel. A serious road collision can result in around 20 emergency services staff attending the scene," Ch Insp Steve Lenney from Dorset, Devon and Cornwall roads policing unit said.
"If someone involved in the collision tests positive for Covid-19, then that is a substantial number of emergency services staff forced into self-isolation and unable to work, which puts a huge strain on all blue-light services, not just the NHS."
Forces reporting an increase in speeding offences also included Northumbria, Leicestershire, Bedfordshire, Cambridgeshire, Hertfordshire and Merseyside.
The all-Wales road safety partnership, Go Safe, said it was "seeing more vehicles exceeding the speed limit to a higher extent" despite a drop of more than half in the volume of traffic.
"The world may have changed, but the speed limit and traffic laws remain the same," Teresa Ciano, from the partnership said.Supt Andy Cox, from the Met Police's roads and traffic policing command, said his team had recorded one driver travelling at 134mph in a 40mph zone.
Inspector Rosie Leech, from the Police Service of Northern Ireland, said, "Despite a 60% reduction in traffic flow, the health advice and business closures, our preliminary figures indicate only a 39% fall in the detection of speeding offences in the four weeks from 17 March, compared to the same period last year.
"However, this still represents a figure of 2,314 people detected speeding... it is particularly disappointing that so many people have decided to put lives at risk by driving at excessive speeds."
Joshua Harris, director of campaigns at road safety charity Brake, said there was "never an excuse for speeding".
He said: "With only essential travel permitted, we would hope to see speeding decline and so the reported increase is deeply concerning.
"We urge everyone to follow government guidance and stay home."
Additional reporting: The Local Democracy Reporting Service