The M5 Southbound between junctions 25 and 26 (Taunton) is expected to stay closed until at least 11am.
Motorists are being advised to take alternative routes.
More top news
A teenager was killed by her step-brother in a "violent struggle" before her body was cut up with a power saw and a knife, a court heard.
We couldn't bring you tonight's news on television because the rugby ran over - but it's all here, with Kylie Pentelow.
Becky Watts allegedly told a friend that Nathan Matthews, who is on trial for her murder, described how he would kill her in 2013.