Isotonitazene, a synethic opioid that is used instead of or in addition to heroin, has been linked to 25 deaths and seven overdoses up to September 2021, the Home Office has said.

And the Home Secretary has asked the Advisory Council on the Misuse of Drugs (ACMD) for advice on the appropriate classification of Isotonitazene under the Misuse of Drugs Act 1971.

Priti Patel also wants advice on two other substances - CUMYL-PeGACLONE, a synthetic cannabinoid, and Diphenidine, which can have ketamine-like effects.

The three substances are currently covered by the Psychoactive Substances Act 2016, which means that supply, but not possession, is unlawful.

She said: "Reports of fatal overdoses linked to this dangerous substance have been deeply disturbing, and I want to act now to ensure no further lives are lost or families torn apart.

"I'm determined to end the misery and destruction caused by the misuse of drugs and will consider the ACMD's expert advice on tightening restrictions on this dangerous substance."

The Home Office is required to consult the ACMD before changing any legislation.

In October last year, the National Crime Agency said it was targeting drug networks that mix Isotonitazene into batches of heroin brought to Britain from Afghanistan.

It came after Public Health England issued a patient safety alert in August, warning of an "unprecedented" number of overdoses potentially caused by heroin mixed with Isotonitazene.

In the US, more than 100,000 Americans died in a single year from drug overdoses, experts estimated.

Health officials say increased use of another powerful opioid, fentanyl, led to the record-breaking number of deaths