THE Zombie drug Spice is now being smuggled into jails stitched inside dead birds, it's been reported.

The news comes as official figures show more than 12,200 ambulances were called to English prisons last year as the drug epidemic takes hold.

And criminal gangs sneaking Spice into prisons are also charging up to 10 TIMES the normal street price leaving inmates and their families in massive debt.

The Sunday Telegraph reveals synthetically manufactured drugs - like Spice and Mamba - have rapidly transformed the behaviour and security in UK jails.

They are now even being concealed inside dead birds before being thrown over jail walls as well as being impregnated onto writing paper and books posted to prisoners.

Inmates have also told how a single sheet of A4 piece of paper soaked in drugs used to be worth about £100. A tiny square inch now commands the same price.

Not surprisingly some governors have now ruled their inmates are only allowed photocopies of letters from friends and families.

The growing demand for drugs in prisons is believed to be one of the key reasons for the surge in the ambulance call outs.

And with each visit costing around £300, the total bill for the emergency calls in 2017 tops £3.6 million.

One former burglar told the Telegraph the new drugs - which are much stronger than cannabis - are known as “bird killer” as they make prison time - known as ‘bird’ - pass in a haze.

“When I first arrived in prison in the 1980’s you would be lucky to find a little bit of cannabis,” he said.

“With the invention of Spice, which is much harder to detect in urine tests because they keep changing the formula, everything has changed.”

Last month, a damning report by the prisons watchdog revealed the extent of the crisis at HMP Birmingham where drugs were smoked openly on landings.

The report prompted the Government to take over the running of the G4S jail as ministers admitted up 20 other jail faced similar problems.

Just last week the Sun Online revealed the true anarchy inside Britain's private jails, as lags take Spice, eat cockroaches, leave staff cowering behind locked doors and set up to 50 fires a week.

A damning report revealed thugs at HMP Birmingham openly used drugs behind bars and roamed around unchecked, as terrified staff locked themselves in their offices.

The filthy conditions were revealed in Chief Inspector of Prisons Peter Clarke's damning report - finding rats, cockroaches were running around communal areas that were covered in blood and vomit.