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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A dry start, with sunny spells developing. However turning cloudier again later, with showers possible by the evening.
After a fine evening with some late sunshine to the end the day, a largely dry and fairly warm night will follow with clear spells.
Any remaining showers will fade, to leave it dry overnight.