MANCHESTER, N.H. – Police in the New Hampshire city of Manchester are warning about an alarming spike in overdoses from the suspected consumption of a synthetic drug called spice.

Police said Tuesday they responded to five overdoses and at least 15 more people were taken to local hospitals for overdose symptoms in the last 24 hours.

Authorities say calls for service related to spice overdoses have continued throughout the day.

Spice is sold in stores as incense. But police say the product – a mixture of herbs and spices typically sprayed with a synthetic compound chemically similar to THC – is often smoked.

Police say the overdoses seem to be associated with a particular brand called Smacked.

Police are working with local store owners to get the product off the shelves.