Useful resources are available from the NYU Child Study Center on “Helping children with developmental disabilities cope with traumatic events“.
The National Child Traumatic Stress Network has a wealth of resources available on trauma and they are continually adding more. One notable example is their publication, “Facts on Traumatic Stress and Children with Developmental Disabilities”.
Statement from the Autism Society: No evidence exists to link autism and premeditated violence. Suggesting otherwise is wrong and harmful to the more than 1.5 million individuals living with autism in the United States. Read their complete statement in regards to the alleged Newtown, CT shooter’s possible autism diagnosis.
Also of note, see the Autistic Self Advocacy Network (ASAN) statement on media reports regarding the Newtown, CT shooting.