Unknown to her, she told police, her 22-year-old son was armed and waiting for the officers when they arrived. Sciullo and Mayhle were shot and killed as they entered the home, and Kelly was killed during a four-hour siege, police said. The confrontation ended with Poplawski's arrest.
As the city began a week of viewings and funerals, new information emerged about the suspect from his Internet postings.
Friends had said he was upset and angry about losing his job a few months ago, feared that President Obama would take away his gun rights, and believed Jews control the news media.
Internet rantings found on a white supremacist website, Stormfront.org, indicate Poplawski was preoccupied with to the idea that Obama would overturn the Second Amendment and that Jews secretly run the country.
He posted a picture of himself without a shirt, showing off a large tattoo of a spread-winged eagle below his collarbone.
Postings on the website after the Pittsburgh shooting encourage people to buy assault rifles because they suspect the arms will be banned in the wake of a string of mass shootings in recent weeks, including one in Oakland, Calif., where four officers were killed and another in Binghamton, N.Y., on Friday when a gunman killed 13 people before killing himself.
In January 2007 Poplawski wrote he was considering getting tattoos of life runes - a common white supremacist symbol also popular with neo-Nazis. It is unclear whether he got the tattoos.
Mark Pitcavage, director of investigative research at the Anti-Defamation League, which tracks killings of law officers by extremists, said Poplawski was chatting on a variety of sites hours before the shootings.
During the battle with police, Poplawski was wearing a bulletproof vest and had a variety of weapons, including an AK-47 assault rifle, authorities said.
His friends, who had been to a bar with him three days before the shootings, said he was not acting unusual. But some said he was upset about being laid off from a job at a glass factory and preoccupied by what he feared would be new restrictions on gun ownership.
One of his friends, Aaron Vire, who is black, said he did not believe Poplawski was racist.
The Marines confirmed that Poplawski had been discharged from boot camp in 2004, but declined to disclose details, citing privacy laws.
