Police have launched a criminal investigation after a chemical was thrown into a property in the early hours of Tuesday morning in South Croydon
Police, Paramedics and Fire crews were all scrambled to Launeston Court on Dunheved Road South just before 2am on Tuesday.
Police have cordoned off the block and are advising residents to stay indoors with theirs windows closed whilst they deal with the on going incident.
Those living at the property are being treated by Paramedics from London ambulance after the callous attack left them with severe chest pains and struggling to breath.
Fire crews have been called with specialist equipment onboard a Detection, identification and monitoring (DIM) unit to carry out test in attempt to identify the chemicals that have thrown into the property.
The Met Police have been approached for further comment.