Martin uses the plot to help improve his mental health and learn how to grow food.
The M5 was closed between Burnham-on-Sea and Bridgwater in both directions causing long delays.
Police said they believed it was an isolated incident and are not looking for anyone else.
Apex Leisure and Wildlife Park is cordoned off and people are told to avoid the area.
The motorway has reopened between J22 and J23, but drivers still face two-hour delays.
Sue Nicholls completed her 14th London Marathon on Sunday in aid of Cancer Research UK.
A man is arrested after he ploughed through stone steps and into several parked cars on a seafront.
The trustees hope the arts project will continue as a voluntary organisation.
Philip Garrett has been jailed for 27 years after for committing 19 sexual offences against children.
