London, June 26 : Prisons are expected to reach full capacity within days, the association for prison governors in England and Wales has warned.

"As this happens, courts and the police will no longer be able to freely and lawfully detain offenders," the Prison Governors' Association (PGA) said on Tuesday in an open letter to political leaders in the UK.

"This will put the public at risk, as people who should be in prison are left to roam the streets," added the PGA.

The latest data released by the UK's Ministry of Justice shows that the prisoner population in the country has reached 87,395, just 1,383 short of the total usable operational capacity, Xinhua news agency reported.

On May 15, the UK government triggered Operation Early Dawn, delaying the start of some court cases across England.