A 17-year-old boy has died and four other teenage boys were taken to hospital after reportedly taking MDMA.
Warwickshire Police said two other 17-year-old boys have been arrested on suspicion of possession of class A drugs with intent to supply and one remains in police custody.
Officers were called to a property in Wetherby Way, Stratford-upon-Avon, in the early hours of Sunday morning (30 June), after being informed the 17-year-old boy had gone into cardiac arrest.
The boy, who was from Stratford, was taken to hospital where he died a few hours later, the force added.
Detective Inspector Lisa Sears from Warwickshire Police said:
At this time, we believe the boys may have taken a type of a drug called 'Mandy', a type of MDMA (also known as ecstasy). We are keeping an open mind as to whether this was a bad batch of drugs, a bad reaction or an overdose. While we are investigating to establish how the boy died we would urge local drug users to be very cautious.