They are wanted for questioning over a range of crimes including murder and rape.
If you recognise anyone in the images, call South Yorkshire Police on 101 to help the force track them down.
1. Mohammed Anwaar
Detectives are asking for your help to trace Mohammed Anwaar, who is wanted for failing to appear at court after being charged with two counts of conspiracy to supply Class A drugs, two counts of money laundering, possession of cannabis and possession of a firearm.
If you see him, please do not approach him but instead call 999 straight away. Any further information can be passed to South Yorkshire Police on 101 or Crimestoppers, anonymously, on 0800 555111 quoting incident number 251 of October 23, 2018.
2. John Eric Wells
Officers in South Yorkshire Police's Major Crime team are asking for help to find wanted man John Eric Wells.
Wells is also believed to go by the names Howard Walmsley and Howard Hemmings.
The 61-year-old, who is originally from South Yorkshire, is wanted in connection with three high value romance frauds, during which three victims lost money totalling more than £400,000.
The offences are reported to have taken place from September 2014 onwards. The victims lived in locations across the UK including Doncaster, Sussex and London.
Police would like to hear from anyone who has seen or spoken to Wells recently, or has information which may help officers with their enquiries. It is possible Wells is currently living outside the UK.
If you see him, or you have any information which may help, call South Yorkshire Police on 101 quoting investigation number A54532/17.
Police in Doncaster want to find John Elliott, who absconded from an open prison last year.
Elliott, 41, left the prison on Sunday, October 11 2020 and failed to return.
He was serving a three-year sentence at HMP Hatfield for burglary.
Elliott is believed to have links to West Yorkshire, as well as Lancashire and Greater Manchester. However, he may have travelled elsewhere in the country and officers are keen to hear from anyone who knows where he is.
Elliott, who may be going by the alias name John Pearson, is described as being of a medium build, with greying hair and a beard. In addition, he has three fingers missing on his left hand, only having his thumb and forefinger.
He is described as having a scar on his right middle finger, as well as scars on his arms. Elliott also has a smiley face tattoo on the top of one of his arms.
If you see Elliott, call 999. If you have information about where he is, or where he has been, call 101 quoting incident number 823 of October 11 2020.
Elliott is now featured on independent charity Crimestoppers Most Wanted website - crimestoppers-uk.org/give-information/most-wanted/appeal?... You can give Crimestoppers information anonymously via their website, or by calling their UK Contact Centre on 0800 555 111.
4. Gary Beck
Police are asking for help to locate 23-year-old Gary Beck.
Beck is wanted in connection with reported offences of possession with intent to supply Class A and Class B drugs, and theft of a motor vehicle.
Beck is described as 5ft 10ins tall and has straight, blonde hair but is known to keep his hair very short or shaved.
Call 101 and quote crime number 14/66403/20.