Police near Philadelphia were hunting a former Marine reservist who authorities say shot and killed six family members and wounded another in a Monday rampage that left dead bodies in three different homes.

A SWAT team storming of a house in Pennsburg, where Bradley William Stone, 35, was believed to be holed up, turned up nothing, The Philadelphia Inquirer reported, and authorities said Monday evening that they did not know his whereabouts.

"As I stand here right now, we do not know where he is," Montgomery County District Attorney Risa Vetri Ferman said shortly after 6 p.m.

Later Monday night, however, police in neighboring Bucks County swarmed an area outside Doylestown after a reported attempted carjacking by a man said to have been dressed in military fatigues and similar in appearance to Stone. But there was no immediate confirmation that the carjacking suspect was Stone.

Ferman said Stone was known to use a cane or walker to assist him, but it's possible he did not need them. Pennsburg is located 48 miles northwest of Philadelphia, and Doylestown is about 27 miles north of the city.
"As I stand here right now, we do not know where he is."- Montgomery County District Attorney Risa Vetri Ferman

Speaking at an evening news conference, Ferman said the rampage began around 3:30 a.m., when Stone allegedly shot and killed Patricia Flick, the sister of his ex-wife, Nicole Stone, at her home in Souderton, also killing Flick's husband, Aaron Flick, and her 14-year-old daughter, Nina Flick. Her 17-year-old son, Anthony Flick, was receiving treatment at a hospital in Philadelphia for a head wound.

Nicole Stone's mother, Joanne Hill, and grandmother Patricia Hill were killed next at their home in nearby Lansdale. Investigators were alerted by a hang-up call to emergency dispatchers, Ferman said.

Then, around 5 a.m., Stone went to Nicole Stone's apartment, located in the Harleysville section of Lower Salford Township, around 5 a.m., investigators said. Brad Stone broke in through a glass door, shot and killed Nicole Stone, and fled with their two children, the woman's neighbors said. Authorities said Stone then delivered the two children, who were unharmed, to a neighbor in Pennsburg.

All three towns are within a few minutes of each other.

Ferman said authorities have recovered Stone's vehicle and his cellphone, adding that authorities did not have information about where he was traveling.

Police with armored vehicles and rifles flocked to Pennsburg after spending several hours at the Souderton home. Several school districts ordered students and teachers to shelter in place, and outside the Pennsburg home, police used a megaphone to try and compel Stone to come out.

"Bradley, this is the police department!" an officer yelled. "Come to the front door with your hands up. You're under arrest." There was no immediate response.

Friends of the family were shocked to hear of the rampage.

"(Nicole Stone) would tell anybody who would listen that he was going to kill her, and that she was really afraid for her life," said Evan Weron, a neighbor of Stone's ex-wife, Nicole Stone.

"Everything started being blocked off, the SWAT was then later called in, then we had the tanks pull up," said Don Smith, describing the scene near his Souderton home.

Brad and Nicole Stone, 33, married in 2004 and filed for divorce in March 2009, according to court records.

The former couple recently sparred over custody of their two children, with Brad Stone filing an emergency petition Dec. 5 and Nicole Stone responding with a counterclaim Dec. 9, according to court records. The outcome of their dispute was not clear.

Nicole Stone's neighbors at the Pheasant Run Apartments in Harleysville said they were awoken Monday morning by the sounds of breaking glass and gunshots.

Weron said Nicole Stone would talk frequently about the custody dispute.

"(Nicole) came into the house a few times, a few separate occasions, crying about how it was very upsetting to her," Weron said.

Stone, whom U.S. Marine Corps records show served in Iraq and held the rank of sergeant at the time of his discharge in 2008, is described as 5-foot-10, weighing 195 pounds, according to the Montgomery County District Attorney's Office. He has an auburn beard and mustache with closely cropped hair.

Anyone with information about Stone's whereabouts is asked to call 911 immediately.

Fox News' Justin Fishel and The Associated Press contributed to this report.