WOBURN, Mass. -- The investigation into the stabbing murders of a mother and her daughter inside their Woburn home stretched out of state Friday.

NewsCenter 5's Jack Harper reported that police have spoken to the former husband of Joanne Presti, who has moved to Delaware. Presti, 34, and her 12-year-old daughter, Alyssa, were found murdered in their home Wednesday.

Presti's landlord, Satnam Singh, met with detectives. She is concerned that the killer is still out there.

"I want to know who is safe. It is my house. I want to see if anyone else came through. I want to know because I am not safe in that house any more," Singh said.

Presti once took out a restraining order on her ex-husband, Thomas Pollack. He remained in Delaware Friday.

"I have very much disagreed with my ex-wife, but I would never do something like this to her, and I would never harm that beautiful girl, Alyssa," Pollack said.

Middlesex District Attorney Martha Coakley said that officials are looking at more recent acquaintances as they continue the investigation.