Dear JC Reardon,
Thank you for posting your request on History Hub!
We searched the National Archives Catalog and located Railroad Accident Investigation Reports, 1911 - 1963 in the Records of the Interstate Commerce Commission (Record Group 134). For more information about these non-digitized records, please contact the National Archives at College Park - Textual Reference (RDT2) via email at Archives2reference@nara.gov.
You may experience a delay in receiving an initial acknowledgment as well as a substantive response to your reference request from RDT2. We apologize for this inconvenience and appreciate your understanding and patience as we balance mission-critical work and the safety of our staff during the pandemic. Please check NARA’s web page about COVID-19 updates for the latest information.
You may also wish to contact local courthouses and law enforcement authorities for Lunenburg, Massachusetts, to inquire about records of any investigations or coroner reports that may have been conducted by local authorities. Also, local public libraries may have back issues of local newspapers with articles concerning the accident.
We hope this is helpful. Best of luck with your research!
There were at least two articles on Newspapers.com about the incident. (To view these links, you would need a paid subscription, to sign up for a free trial, or free access through some local libraries or other such entities.)
29 Jan 1918
Three Camp Devens Workmen Killed – Four Others Injured in Auto Struck at Lunenberg
Fitchburg Sentinel (Massachusetts)
29 Jan 1918
Main headline on the front page, continuing on page 9
Three Killed as Auto and Engine Crash at Crossing
There may be articles in other papers in other locations, as well.