Connecticut became the 5th state to join the United States of America.
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Adam Lanza shot and killed 20 children and 6 adults at the Sandy Hook Elementary School in Newtown, Connecticut.
The first ballistic missile submarine was launched from Groton, Connecticut, US.
The first commercial helicopter, Sikorsky S51, had its first test flight.
One of America's oldest documented highways was completed on this day in Connecticut, USA.
Automatic street lights first appeared in New Milford, Connecticut, US.
