The number of children suffering from suspected carbon monoxide poisoning is increasing, according to a new report.
The research, by awareness campaign group Project SHOUT, shows that more than 500 cases involving under 18s were reported last year.
Poisoning by the odourless and colourless gas, dubbed the silent killer, causes about 50 deaths a year in the UK.
The charity says the figures, obtained through a Freedom of Information request, show an alarming increase in the number of cases since 2015.
The worst-affected areas for children are London and the East Midlands (a 28% increase), the West Midlands (58%) and East Anglia (211%).
The West Midlands showed the highest increase across all age groups, with reported cases up by 91%.
Carbon monoxide (CO) is produced when fuel does not burn properly in gas and oil boilers, gas hobs and fires, log burners and open fires and barbecues.
The only way to detect it is with an alarm similar to a smoke detector.
CO detectors, which cost less than £20, to be in every home.
It is estimated that 12 million homes are without CO alarms, and many people who do have them say they never test them to check they are still working.
It is recommended that homeowners and tenants should have their appliances installed and serviced by qualified Gas Safe registered engineers and that every home should have at least one CO alarm.