Sudden death, Mount Lindsay

A man has died and another is in a critical condition after suffering an adverse reaction from an as-yet unidentified substance in Mount Lindsay.

Police were called to a large party at an address on a property south of Hardgrave Road around 10.20am.

It appears there were upwards of 100 people at the party, with an initial estimate indicating there may have been as many as 500.

Several people began to show an adverse reaction and required urgent medical assistance.

A man was declared deceased at the scene, while another has been airlifted by helicopter to the Gold Coast University Hospital.

Another man was also treated for the same type of adverse reaction.

Detectives from the Logan District Criminal Investigation Branch are on the scene.

Police will prepare a report for the Coroner.

If you have information for police, contact Policelink by providing information using the online suspicious activity form 24hrs per day at www.police.qld.gov.au/reporting.

Report crime information anonymously via Crime Stoppers. Call 1800 333 000 or report online at www.crimestoppersqld.com.au.