A Boston man has been arrested for allegedly killing the mother of his three children in a South End apartment, according to officials.

Eric McPhail has been charged in connection with last month’s murder of Shantel Gillespie, the 30-year-old mother of his three children.

Gillespie was found in an apartment at 390 Harrison Ave., in the South End, on Dec. 12.

Investigators during their initial investigation believed that Gillespie’s death was a homicide, and that the killing was not random.

McPhail is expected to be arraigned on Wednesday.

Suffolk DA Kevin Hayden said in a statement, “This was a lengthy and thorough investigation and I’m grateful for the work of all involved to bring this suspect forward to answer for Shantel Gillespie’s tragic death.”