WOBURN - Officials believe murder victims Joanne Presti, 34, and her daughter, Alyssa Presti, 12, were not targeted at random, but say no one has been ruled in - or out - as a suspect.

Middlesex District Attorney Martha Coakley said during a press conference Thursday afternoon that although "we urge folks to be cautious in Woburn or anywhere" when at home or in their car, the citizens of Woburn should not be worried their is an attacker on the loose who might be looking for another victim.

"We do not, at this time, believe these attacks were random," Coakley said, noting investigators did not see signs of forced entry or signs of a struggle, leading them to believe the attacker knew the victims .

However, Coakley said, should the investigators see any evidence to the contrary, her office and the Woburn Police would alert the public immediately.

Presti and her daughter were found murdered in their home Wednesday afternoon. Coakley said investigators believe both victims were killed at about the same time, sometime between 10 p.m., Sunday, and noon or earlier Monday.

A neighbor reportedly called Presti's parents after being unable to reach her even though her minivan was in the driveway. Her parents made the gruesome discovery and called police.

Presti's 2 1/2-year-old son Sean was found in his crib, reportedly hungry and dehydrated but otherwise unharmed. He was taken to Winchester Hospital and released Wednesday night to the custody of a foster family, said Denise Monteiro, a spokeswoman for the state Department of Social Services.

A third child, a 9-year-old son, reportedly lives with his father, Frank Martineau, in Revere.

News media have focused on the three fathers of Presti's three children, but while Coakley said investigators certainly wanted to talk to them and anyone else who knows or is related to the family or who could provide information about anyone with possible motive or opportunity, she reiterated that no one has been ruled in or out as a suspect.

At the request of Massachusetts authorities, the New Castle, Delaware Police Department tracked down Thomas J. Pollak, whom Presti divorced in 2002. In 2001, Presti obtained a restraining order against Pollak, saying he hit her with a telephone while she was pregnant with their son Sean, and that she was afraid of him.

In a sworn statement filed for the restraining order in September 2001, Presti accused Pollak of trying to choke her — and then pulling out the phone wires to prevent her from calling for help.

"He has threatened to burn my vehicles and take my baby away from me," she wrote in the document filed in Woburn District Court.

In a document filed in October 2001 to amend the restraining order, Presti wrote: "I am having him served with divorce papers and he said he's planning on coming back and I'm scared because he's abusive and he was supposed to go to counseling and never did."

The restraining order against Pollak expired in 2002 without being renewed and no violations of the order were reported, Coakley said.

"We interviewed him (Pollak), and he was released," said Cpl. Trinidad Navarro, county police spokesman. "I can't comment on any aspect of the interview."

However Pollak, 38, told the Boston Herald from his home in Delaware that he had not left the state during the time when police believe the killings occurred and that he has store receipts and several witnesses to prove it.

"I had very much disagreed with my ex-wife. But I would never do something like this to her," Pollak said. "And I would never harm that beautiful girl, Alyssa. She was beautiful and she was sweet and she was kind, and it rips my heart apart."

A D.A.'s office spokesman this morning said again, no one had been ruled in or out.

Alyssa Presti was the daughter of former Boston Bruins hockey player John Carter. Presti and Carter were not married, and Carter — who played for the Bruins in the late 1980s and early 1990s until an eye injury ended his career — said he had met the youngster only once.

"This is just awful," he told The Boston Globe from his home in Woburn.

He said he told police that he had no knowledge of the killings, and that they had not suggested he was a suspect.

"I don't know much of anything, other than things I'm hearing in the media," Carter said. "I'd like to know what happened, like anyone else. That poor little girl."

At the press conference Thursday at the Woburn police station Coakley declined to comment on who investigators had spoken with, although she did confirm they had spoken with Carter because he had commented publicly that police had spoken with him.

"I will say that everyone we've spoken with to date has been cooperative," Coakley said. "(But) we have no reason to label anyone as a suspect."

The Office of the State Medical Examiner completed autopsies on both victims Thursday, ruling both deaths homicides.

Coakley announced at a press conference Thursday that the report indicated Joanne Presti had suffered multiple stab wounds and blunt head trauma. She said the Medical Examiner's Office could not immediately determine in what order the injuries occurred or which ultimately proved fatal, but that either was sufficient to kill her.

Initial reports from the scene were that Joanne Presti had "no obvious trauma," though that appears to be because she was found face down on the couch and investigators had yet to move the body.

A press release issued later in the day confirmed that Alyssa's neck had been cut. She was found lying on the floor in her upstairs bedroom, Coakley said.

Coakley said Thursday afternoon that although Joanne Presti's clothes were in disarray, initial indications are that she was not sexually assaulted, though further tests were needed.

"We would like to rule that in or rule that out as soon as possible," Coakley said.

Asked later if there had been a current boyfriend in Joanne Presti's life, Coakley said investigators did not know.

Coakley said investigators recovered several possible weapons from the house, but said investigators did not have any positive evidence that any of them were used in the murders.

Coakley spokesman Seth Horwitz said this morning officials had no new information on the weapons test results to release.

Also during the press conference, Coakley said authorities believe the murders were the work of a single attacker, but said it was possible there was another assailant.

Coakley urged parents with children to take advantage of resources available to help them talk with their children about the tragedy to allay their fears and deal with their grief, particularly if they knew Alyssa or went to school with her.

There are counselors available at the schools, she noted.

Woburn and State Police investigators were still at the West Woburn Totman Drive duplex Friday morning continuing to comb the scene for evidence.