A young boy is in critical condition after his nativity costume was sparked by a candle last night.
London Fire Brigade have warned parents and teachers away from using real candles around children after the horrific accident.
The boy, believed to be aged between 7 and 10, was rushed to hospital via air ambulance after he was seriously burned.
His condition is said to be critical but stable.
Witnesses said his costume was "completely engulfed in seconds" after he fell forwards while holding a candle at Our Lady of the Annunciation Church in Croydon.
Two adults, thought to be teachers, were also burned and taken to hospital via road.
London Fire Brigade assistant commissioner for fire safety Dan Daly said: "This horrific accident is a stark reminder of the risk real candles can pose.
"They are a completely unnecessary hazard when it comes to children and school plays.
"Sadly this isn't the first time we have seen clothing and costumes set alight by candles and people need to recognise the risk and prevent these incidents from happening again.
"People should not be using real candles - especially around children, costumes and decorations - when there are far safer alternatives available."
The fire chief advised parents to choose LED candles over flame ones and to be particularly careful around potentially flammable Christmas decorations and costumes.
The child's father was seen crying and heard shouting "my son", a local shopkeeper told The Sun .
Noel Campbell, head teacher of St Thomas Becket Catholic Primary School where the boy is a pupil, said: "Our whole school community is devastated by the incident that occurred at our carol service yesterday.
"Our thoughts and prayers are with the child and his family at this difficult time.
"Following this incident, our pupils, staff and families are being given support."
London Ambulance Service attended the scene on Wednesday afternoon and later called officers from the Metropolitan Police, who are not investigating the incident.
The Health and Safety Executive was also informed.
Croydon Council will now review the incident with the school, the Archdiocese of Southwark and London Fire Brigade.
A council spokesman said: "Our thoughts are with all those affected by this very sad incident and we are supporting staff, pupils and the wider school community.
"We will be working closely with the school, the diocese and London Fire Brigade to review the circumstances to minimise the risk of anything like this happening in the future."
In 2016 TV presenter Claudia Winkleman raised concerns about the dangers that cheaply made costumes posed to children when her daughter's Halloween outfit went up in flames.
Her then eight-year-old, Matilda, was left with severe burns on her leg.
