Police sealed a road in Wythenshawe after a “chemical issue” raised concerns about a man’s health.
Residents reported seeing officers on Sale Road in North Moor, who wore fire retardant suits.
It is understood that the accident affects a man’s health and there is no wider danger to other residents.
There are also firefighters, with four fire trucks and a team of “dangerous materials” on site.
Emergency services were called for the first time shortly after 9 am today.
As the investigation continues, the property in question remains sealed.
Man is treated by paramedics.
An eyewitness said: “The North Moor police in biohazard clothes. There are a lot more police and firefighters here, then this morning.”
Another said: “There are a lot of police, ambulances and firefighters. They recorded the street.
“There are many here. I am outside one of the houses that has been registered. They said there is a chemical problem, that’s all they told us.”
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