Two people arrested in connection with the death of a six-year-old girl were released without charge on Friday after a post-mortem examination found no suspicious circumstances.
The 30-year-old man and 40-year-old woman, both from Gosport in Hampshire, were held on suspicion of murder after the girl was found "fitting" at a holiday campsite in the New Forest, Hampshire.
She suffered a cardiac arrest early on Friday morning and was rushed to Southampton General Hospital but was pronounced dead a short time later.
The Holmsley campsite was the scene of intense police activity all day as scene of crime officers examined the family-sized tent the girl was staying in.
Investigations have been continuing to find out exact circumstances of the death.
A Hampshire Police spokeswoman said: "The results of a post-mortem examination conducted at Southampton General Hospital have indicated that there are no suspicious circumstances.
"The arrests made this morning were necessary as a result of a report from experienced medical professionals.
"The girl's death is no longer being treated as suspicious but a tragic incident. An investigation into the cause of the girl's death is ongoing.
"As with all investigations into the death of a child we will now be working with partner agencies to support the family throughout the investigation process."
Families staying at the camp reported being woken up by a woman screaming just after 12.30am, followed by someone repeatedly sounding a car horn, before the arrival of the emergency services.
Police were called by paramedics who found the girl was "fitting and not breathing". Her mother and father were reportedly giving her CPR when medical staff arrived.
The two people who were arrested were questioned by detectives for most of the day as around 40 officers worked on the circumstances surrounding the death.
The Camping and Caravanning Club's director general Robert Louden said: "We were saddened to hear the tragic news earlier today and have since been assisting the police with their ongoing investigations.
"On behalf of the club I would personally like to thank our holiday site managers, assistants and campers on site at Holmsley for their full co-operation and compassion, and our thoughts are very much with the little girl's family and friends at this difficult time."
The campsite hopes to reopen on Sunday for new arrivals and police were expected to remain in the vicinity to reassure visitors to the site and the local community.
The girl's identity is expected to be released on Saturday.