Two men have been arrested by officers investigating suspected drugs-related deaths of six people in Essex.
Three men and three women from Southend, Leigh-on-Sea, Canvey Island and Westcliff-on-Sea have died in the period between 28 July and 30 July.
Tests are being carried out to identify the substance or substances involved in the deaths.
A 26-year-old from London and a 29-year-old from Grays were arrested in Barking on Friday afternoon.
They are being held on suspicion of possession with intent to supply Class A drugs.
The force has urged anyone with information about the sale of Class A drugs in the county to contact them.
Public Health England has urged drug users to be extra careful and to not use alone and to test a small amount first.
“They need to look out for each other and be alert to any signs of an overdose, such as lack of consciousness, shallow or no breathing, ‘snoring’, and blueing of the lips and fingertips,” it said.
“They should immediately call for an ambulance and use any available naloxone if someone overdoses on opioids. We strongly advise all dependent drug users to get support from local drug services.