Britain's growing CCTV network could be a target for hacking attacks, a watchdog has warned.
Surveillance camera commissioner Tony Porter flagged up the possible risk of intrusion on the public by "individual and state actors".
He pointed to a major cyber incident in Washington DC in January last year where more than 100 cameras were infected with ransomware.
Mr Porter said: "The risk potential for intrusion on citizens has significantly increased both by lawful operators of surveillance camera systems and those individual or state actors who seek to hack into systems.
"Cyber security has moved to the top of the security agenda."
Publishing his annual report for 2016/17, Mr Porter said surveillance cameras are not always recognised as potential hacking targets.
He told the Press Association: "As we move from analogue to digital surveillance, most cameras are plugged into corporate IT networks.
"If your camera is not suitably protected you are potentially opening up a back door for organisations that choose to hack.
"What we are saying is that cameras are potentially your vulnerable point. You must ensure that you apply the same level of IT security to your cameras as you do to your mainframe.
"There is a whole host of areas where data could be accessed through insecure surveillance networks."
Britain is seen as having one of the most extensive CCTV networks in the world, and the commissioner's report indicates that it continues to grow.
Research in 2013 estimated the number of cameras in the UK at up to six million.
Mr Porter said: "I believe the figure may now be much higher than this estimate, given the proliferation of cameras being adopted by such a wide range of organisations and the increasingly intrusive nature of new and emerging technologies.
"I am concerned at the incrementally intrusive development of surveillance cameras in the everyday lives of citizens."
The assessment also called for the Automatic Number Plate Recognition (ANPR) system to be placed on a statutory footing.
ANPR is one of the largest non-military databases in the UK, with around 9,000 cameras nationally that capture between 25 million and 40 million pieces of data per day, while up to 20 billion "read" records are held.
Mr Porter described this activity as "formidable", saying: "The nature of its capabilities to intrude on privacy by building patterns of travel and the provision of imagery should not be underestimated.
"I firmly believe that this system needs legislative oversight and that the Government should place this system on a statutory footing."
The watchdog noted that arguments have been advanced that the number of manufacturers of number plates should be limited.
But he suggested a system of stricter controls may be needed, similar to the production of driving licences and passports.
Mr Porter also said he understood there are issues with inaccurate location of ANPR cameras or cameras failing to report their correct location, adding: "I think this might have a negative impact on future prosecutions."