Seven people ended up in hospital after attending the Big Day Out concert in Auckland yesterday.

St John Ambulance says the packed out mosh pit (the area in front of the stage), and the use of herbal party pills proved too much for some.

One person has head injuries and there were two overdose cases from party pills.

The heat led to more incidents of exhaustion and dehydration than in past years.

Several arrests were made.

Nearly 40,000 people attended the 12 hour event at Ericsson Stadium.