Investigators say they hope the toxicology tests will show whether the 32-year-old woman deliberately killed herself and her children, or if they accidentally died in the closed vehicle in the heat.
Police hope to release the names of the three victims after they've notified the woman's immediate family members.
As we've reported, the woman was originally from Guyana but recently moved to Hagerstown, Md., from West Virginia.
The investigation remains ongoing.
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