Cordon is in place while chemical is identified. Ambulance staff are treating nine people.
M6 closed in both directions between J3 A444 / B4113 (Nuneaton / Bedworth / Coventry) and J4 M42 / A446 (Coleshill), congestion on M6 to J2 M69 / A46 (Coventry) Northbound.
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Rain moving east, sunshine and showers Thursday.
Rain overnight, heavy in places.
The oldest trophy in English football has travelled to Alvechurch Football Club, ahead of the team's match against Hanley Town this weekend.