The collection is comprised of captured websites and Twitter data related to the mass shooting that occured at the Route 91 Harvest Festival in Las Vegas, Nevada on October 1, 2017. Captured websites are primarily comprised of articles and news stories from local, national, and international news media outlets. Websites were captured periodically from 2017 to 2018. The collection also includes Twitter data associated with the October 1 shooting that were captured via concurrent queries to the Twitter API for all Tweets containing the term “vegas” occuring September 29, 2017 to October 7, 2017. Also included are files containing tutorials for how to curate and analyze Twitter data which reference the 1 October Twitter dataset for illustrative purposes.