PHILADELPHIA (CBS) – Prosecutors say the suspect in a deadly rampage near Philadelphia has been killed by SWAT team members after they entered a suburban home.

Authorities identify the suspect as 51-year-old Mark Geizenheyner. Montgomery County district attorney Risa Ferman says he’d been planning for more than a year to rob a Gilbertsville house and kill the owner Paul Shay– whom he knew– when he knocked on the door Saturday and said, “Guess you never thought you’d see me again.” (see related story).

“We understand that he was surprised by the number of people there. Still, we believe, he took those shots in any case and fled the residence,” said Ferman.

Authorities say Geisenheyer shot five family members in his neighbor’s home, killing the nephew and the two-year-old, before he fled.

He ended up at a home in Trainer but the resident alerted police, who surrounded the house and ultimately broke in and shot Geizenheyner. Ferman says Geizenheyner was not going to leave the house alive.

“He knew what he had done, he knew the consequences would be extraordinary and he was not willing to face the consequences.”

Authorities say they tried to negotiate and flush out Geisenheyer with tear gas, but he told police he was not going back to prison. Delaware County District Attorney G. Michael Green says Geisenheyner was killed after hours of negotiations failed.

Reported By Pat Loeb, KYW Newsradio; Oren Liebermann, CBS 3

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