(CHICAGO) Detectives have opened a homicide investigation after two people were found dead in a Ukrainian Village home following a five-hour barricade situation Tuesday, police said.

Officers responded about 5 p.m. to a call of a domestic-related shooting in a building in the 800 block of North Wolcott, according to Chicago Police. Someone refused to come out of the apartment, and the police SWAT team was called to the scene.

SWAT team members made entry into the home about 10 p.m. and found a woman and man both dead inside, police said. The Cook County medical examiner’s office did not immediately confirm the fatalities.

A police source said the deaths may have resulted from a murder-suicide, but additional information was not available. Area Central detectives are conducting a homicide investigation.