Investigators initially said that all three of the women suffered gunshot wounds, but later it emerged that the mother had been stabbed to death.
Senior police sources said he was armed with a pistol and had waved it at officers several times during the siege.
The victims were identified as 18-year-old Kylie Pifer, 21-year-old Taylor Pifer and their mother, Suzanne Taylor, Loeding said.
A section of Valley Forge Drive was blocked off by police, but a crowd of about two-dozen onlookers gathered across the street around midnight to watch the situation. A woman who was in the house is now outside and unharmed.
Suzanne Taylor (center) with her two daughters Kylie and Taylor (unclear which is who) who were found dead in their OH home on Sunday night.
Cleveland19 reported Monday, citing police, that the mother and daughter were still alive Saturday afternoon and were killed sometime that evening. The bouquet was still outside the home Sunday.
No arrests have been made, but Loeding said police have been looking at persons of interest.
Police told residents to remain in their homes as the standoff continued.
"Taylor was majoring in fashion design, while Kylie was involved in theater and was majoring in forensic science", the stepmother told WGHP-TV.
A Cleveland 19 reporter had come in contact with the man via Facebook earlier in the day, as a result of her reporting on the story.
Told Pifer, 'They were great kids... and this totally, totally blind-sided us'. Dave Loeding of the North Royalton Police Department said at a news conference.