MIDDLESBROUGH, England — Two men aged 23 and 31 remain in police custody on suspicion of murder following a house fire early Wednesday that killed seven-year-old Valentina Foster and her 34-year-old aunt, Natalie McDonald, in the Grangetown area near Middlesbrough.

Cleveland Police said they are investigating whether the fire was a gangland revenge attack tied to a separate incident. On Saturday, a stolen Volkswagen Passat involved in a crash on the A66 killed five young men and two police officers. Police indicated the vehicle was allegedly chasing a rival gang as part of an ongoing violent feud.

Officers arrived at the property at 5:23 a.m. Wednesday. Valentina and Ms. McDonald were confirmed dead at the scene. Another woman remains hospitalized in critical condition, while three others received treatment for non-life-threatening injuries.

Police said they have not ruled out any connections to wider organized crime. The scene has not yet been fully examined. The property, about one mile from the A66 crash site, sustained severe damage; the roof was destroyed but the structure did not collapse.

Lisa Kirton, Ms. McDonald's mother, said her daughter was "a beautiful, bubbly person who everyone knew" with "a heart of gold who would give anyone anything." Ms. Kirton, who lives across from the house, said she woke at approximately 5 a.m. and saw people being pulled from the burning building. After waiting about three hours for news, police told her that her daughter had died.

Ciara Randle, 10, a neighboring resident, said she woke to screaming, barking dogs and sirens "very early" as the sun was rising. She said she and her mother were "very shocked" by the incident.