The London police are sending out a warning after two seized drug samples tested positive for carfentanil.

The deadly synthetic opioid is 100 times more power than fentanyl or 10,000 times more powerful than morphine, police say.

“This is a turning point in the local drug crisis and it’s not a turn for the better. I am sad for the effect this will have on the most vulnerable people in our community; even for first time users, it’s like playing Russian roulette,” said Dr. Chris Mackie, Medical Officer of Health with the Middlesex-London Health Unit.

Mackie said health officials have been anticipating this crisis and are expanding the distribution of naloxone. As well consultations about supervised consumption sites are underway.

Police say in 2017, there have been 23 confirmed seizures of fentanyl, a 460 per cent increase from the five confirmed fentanyl cases in 2016.

Only two milligrams of carfentanil powder, equivalent  to a grain or two of salt can be lethal.

The drug can also be mixed with other drugs and cannot be detected unless tested in a laboratory.

“People should never use alone and they should always have Naloxone with them,” Mackie said.

If you suspect that an overdose has taken place, call 9-1-1 for medical assistance.