iStock/Thinsktock(NEW YORK) — Some of the deadliest mass shootings in the U.S. this year prompted widespread national horror, including the Parkland, Florida high school shooting and the massacre at the Tree of Life synagogue in Pittsburgh.
News of other mass shootings, however, seemed to have only reached local audiences. There were a number of incidents where spouses or former spouses killed their partners (and sometimes their children) in Texas, Delaware, Tennessee, Maryland and California.
The FBI defines a mass shooting as an incident where four or more people — not including the suspect — are killed. While there is no publicly accessible federal tracker of such incidents, various groups and watchdog organizations keep their own lists, often using different definitions of what qualifies as a mass shooting.
For the list compiled by ABC News below, the incidents took place over the course of one day and involved four or more victims, not including the suspect. For instance, shooting sprees that spanned longer amounts of time were not included on this list.

As of Nov. 28, there were at least 18 shootings that fit these parameters.
There are hundreds of other deadly shootings that took place across the U.S. this year that don't fit these conditions, including some that received national attention, like the shooting at a Maryland Rite Aid, or the shooting at a Chicago hospital. In both of those incidents, three victims were killed and the respective suspects also killed themselves.
But whether they made national headlines or not, the common thread among the 18 incidents below was that they happened in the first 11 months of 2018.

1. Jan. 28: Shooting at a Pennsylvania car wash, four victims
2. Jan. 28: Shooting at an apartment in Pennsylvania, four victims

3. Feb. 10: Domestic shooting spree in Kentucky, four victims

4. Feb. 14: Marjory Stoneman Douglas High School shooting, 17 victims
5. Feb. 26: Shootings at gas station and a home in Detroit, four victims
6. April 22: Waffle House shooting in Nashville, Tennessee, four victims
7. May 17: Domestic violence incident in Texas, four victims
8. May 18: Santa Fe High School shooting, 10 victims
9. June 10: Domestic violence incident in Florida, four victims
10. June 28: Shooting at Maryland newspaper office, five victims

11. July 9: Domestic violence incident in Delaware, four victims

12. July 27: Domestic violence incident in Texas, four victims

13. Sept. 12: Domestic violence incident in California, five victims

14. Sept. 17: Domestic violence incident in Maryland, four victims

15. Oct. 13: Shooting at a birthday party in Texas, four victims
16. Oct. 15: Mother kills teenage children and herself in Tennessee, four victims
17. Oct. 27: Shooting at a Pittsburgh synagogue, 11 victims
18. Nov. 7: Shooting at a California bar, 12 victims

Copyright © 2018, ABC Radio. All rights reserved.