The father of a seven-year-old boy who died after falling ill in a flood-hit town has started legal action in a bid to find answers.
Zane Gbangbola and his parents became ill at the family home in Thameside in Chertsey, Surrey, in February and were taken to hospital, where he later died.
His father, company director Kye Gbangbola, remains paralysed from the waist down following the incident in which he suffered a cardiac arrest, lawyers said.
In the early hours of Saturday February 8, Kye Gbangbola, Zane, and Zane's mother Nicole Lawler, were all taken ill, and an ambulance was called with all three taken to hospital. Both Mr Gbangbola and his son had suffered cardiac arrest.
A post-mortem examination into the death of the seven-year-old found ''no clear cause of death''.
Surrey Police have refused to be drawn on whether carbon monoxide poisoning from a generator pumping out flood water from his home may have been to blame.
A Surrey Police spokesman said after the post-mortem: ''There is no clear cause of death and tests are continuing."
Today a spokesman said: "The investigation into Zane's death remains ongoing. A post-mortem examination carried out on Tuesday 11 February did not establish a clear cause of death and we await the results of further tests which are expected to take a number of weeks.
"It would be wrong to speculate on the cause of death at this stage. Officers continue to provide updates to Zane's family. We fully appreciate this is a difficult time for the family as we wait for updates."
The incident occurred during the floods, which consumed the area earlier this year.
Mr Gbangbola believes there needs to be a thorough investigation into the potential effects of recent disturbances to a piece of neighbouring land which has now been discovered was formerly a landfill site, lawyers said.
Lawyers for the couple are now investigating the possibility that the house had been affected by hydrogen cyanide.
Mr Gbangbola's lawyer Vijay Ganapathy, from law firm Leigh Day, said: "There seems to have been a rush to judgment that this was carbon monoxide poisoning. There is a possibility that floodwater could have come through the contaminated land and into Mr Gbangbola's house.
"We understand that the presence of hydrogen cyanide necessitated the clearance of neighbouring properties and a public health warning for those in the area feeling unwell to seek urgent medical assistance.
"If this is the case then many more people could be at risk and a full investigation of the ex-landfill site needs to be undertaken as a priority."
Mr Gbangbola said: "We have very real concerns for the welfare of our neighbours and the wider public in flood affected areas/regions as well as burning questions which come when you lose a child inexplicably.
"We are not looking for someone to blame; rather, we are looking to understand what happened and whether this could happen again.
"There can be no stone left unturned when dealing with such potentially fatal consequences."
He added: " We would like anyone with information to speak to Leigh Day in confidence, it is essential agencies that are meant to protect the public do the right thing.
"Walls of silence and misinformation are unhelpful to finding the truth about Zane, and protecting those at risk.
"Do not allow a child's death to be swept under the carpet."
In a Surrey Police news release issued on February 8, Chief Superintendent Dave Miller said: "We cannot rule out that there may be a link to flooding in the local area and whilst the investigation is ongoing local residents should follow sensible precautions."
On February 9, he said: "The information we have received from our partners at the Environment Agency in relation to the preliminary water testing gives an indication that there is no link between the quality of water at the location and the boy's death."