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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Over 15,000 people were expected to turn out for the Vaisakhi festival celebrations in Leicester today.
Most areas will be mainly dry with prolonged clear spells developing, leading to patchy frost in some places
Dry and largely clear overnight, with frost developing in some areas.