[8] On November 10, 1985, a hunter found a metal 55-gallon drum near the site of a burned-down store at Bear Brook State Park in Allenstown, New Hampshire.

In February 2020, it was announced that DNA analysis suggested the child was primarily Caucasian, with slight Asian, African, and Native American heritage.

[22][23] In the early days of the investigation, authorities publicized the case in the United States and some parts of Canada.

In June 2013, new versions of the victims' facial reconstructions were created by the National Center for Missing & Exploited Children (NCMEC).

[24] In November 2015, NCMEC released a third set of reconstructions of the four victims at a news conference at the New Hampshire State Attorney General's office.

Other forensic information showed that the woman and children lived together in the Northeastern United States between two weeks and three months before their deaths.

[26][27] In 2019, however, it is stated that the nonrelated child most likely originated from Arizona, Texas, California or Oregon, although additional locations cannot be excluded.

[20] In January 2017, it was announced that the disappearance of Denise Beaudin, a woman from New Hampshire who had been missing since 1981, was connected to the Bear Brook murders.

[29] However, it was not until 2016 when, with the help of detective Peter Headley of the San Bernardino County Sheriff's Office and genetic genealogist Barbara Rae-Venter, "Lisa" was discovered to be Beaudin's daughter.

[31][32] Due to the proximity between Manchester where Beaudin disappeared and Allenstown where the barrels were found, New Hampshire authorities suspected the cases were connected.

He had been convicted and sentenced under another alias, Curtis Kimball, for the 2002 murder and dismemberment of his wife at the time, Eunsoon Jun, a chemist in California.

Two months later, Robert Evans was confirmed as Terry Peder Rasmussen, through Y-DNA testing from a DNA sample contributed by one of his children from what is believed to be his first marriage.

[37] Rasmussen, known as the Chameleon Killer, is believed to have used "at least five different aliases in a decades-long run of crimes across the country, including at least five homicides, and likely more.

In October 2018, a librarian and web sleuth Rebekah Heath, who was looking for possible identities of the Bear Brook victims, found the post.

She also found that Sarah's mother, Marlyse Honeychurch, had an older daughter with her first husband, and that their ages matched those of the three related Bear Brook victims.

Significantly, one of Sarah's relatives who Heath contacted mentioned that Honeychurch had married a man with the last name Rasmussen.

[39][30] On June 6, 2019, New Hampshire investigators held a press conference regarding the case and revealed the identities of three of the victims.

[15] The fourth victim's identity is not yet known, but investigators stated that through advanced DNA testing they could confirm the child was Rasmussen's.

[41] In February 2020, a new rendering of the fourth victim was released by the National Center for Missing & Exploited Children and New Hampshire State Police.