Mohammed Islam and Mahbub Hussain, both 25, phoned potential victims claiming to be fictional police officers Sgt Anthony Matthews and PC Gary Lambert.
They would instruct their victims to call back on 999 to verify their identity as police officers, but would instead keep the line open so that the second fraudster could verify that the first was a legitimate police officer.
The fraudsters then convinced people to believe that they were assisting with covert police investigations.
In most cases, the victims were told that a fraudster impersonating a relative had been arrested.
Those receiving the calls from Hussain and Islam were then told to not tell anyone about their conversations but were asked to withdraw large sums of money for “fingerprinting” to assist the police in apprehending suspects.
Some were also asked to send money although these transfers were prevented by genuine banks.
Hussain and Islam made numerous phone calls to landlines across the UK, with 16 being used as witness statements to the police.
Between May 9 and May 21 last year the pair spent 60 hours on the phone to victims with one elderly victim being kept on the phone for eight hours.
While the total amount requested by the fraudsters amounted to £87,000, most people recognised the scam before parting with their money so only £9,000 was actually received by the fraudsters.
Mohammed Islam (Image: Thames Valley Police) Islam, of Wroxhall Road in Dagenham, and Hussain, of Buckle Street in Whitechapel, were both convicted by a jury of conspiracy to commit fraud.
Islam was sentenced to a total of three years in prison whilst Hussain was jailed for two years.
Mahbub Hussain (Image: Thames Valley Police) Det Con Patrycja Lesiakowska said: “The defendants in this case showed a disregard for the wellbeing of the victims, targeting some of the most vulnerable members of our community.
“Their elaborate scheme to impersonate police officers and deceive victims into handing over money was both cruel and calculated.
“This conviction highlights our commitment to bringing such criminals to justice and protecting victims from fraud.”
Islam was also given a serious crime prevention order restricting his mobile phone and vehicle use for five years after his release from prison.