Eight people have been taken to hospital after an “unknown substance” was sprayed through the window of a house.
A man wearing dark clothing sprayed the substance into a property on Skydmore Path in Slough before running away.
The victims felt nauseous and were taken to hospital following the attack just after 17:00 BST on Sunday.
Thames Valley Police said it was not an acid attack.
The force said the victims were taken to hospital as a precaution and did not suffer any serious injuries.
Berkshire Fire and Rescue Service also attended the scene.
The police are appealing for witnesses to come forward.
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