Police issued a safety warning to nearby residents after a haul of potentially dangerous chemicals was uncovered during a raid on a house in Sutton.
Officers executing a drugs warrant at an address in Sutton Road made the discovery.
The raid - which took place at around 7.30pm on Wednesday - resulted in a 61-year-old man and a woman aged 39 being arrested on suspicion of manufacturing drugs.
During a subsequent search police discovered a large quantity of chemicals both in the house and in the rear garden.
A force spokesman said: “Mersey Fire and Rescue Service are in attendance at the scene to examine the chemicals and determine if there is any risk.
“In the meantime as a precautionary measure Merseyside Police is advising residents in the Sutton Road area to keep their doors and windows closed.
“Road closures have been put in place at Sutton Road and motorists are advised to find alternative routes.”