A romantic relationship that soured sparked a Manassas man to fatally shoot his ex-girlfriend and two other people and wound three more in a shocking spate of violence that shattered a close-knit neighborhood, authorities said Friday.

Jose Oswaldo Reyes-Alfaro, 37, a Salvadoran national who was in the country illegally, was armed with a .38-caliber revolver when he went to the Hood Road townhouse he shared with Brenda Ashcraft, 56, just after 7 p.m. Thursday, according to police and court records. After fatally shooting Ashcraft's son and wounding two other family members, including a teenage girl, he shot Ashcraft in the head as she tried to dial 911, police said.

Reyes-Alfaro then went to a house just blocks away and used the last bullet in the revolver to kill his friend Julio Cesar Ulloa, 48, court records say. Using a large knife or machete, he cut Ulloa's 77-year-old landlady in the head, the records say.

"We're not sure what the straw was that broke and led to all of this violence," said one police official who spoke on the condition of anonymity because he was not authorized to speak to the media. He said that Reyes-Alfaro and Ashcraft had a "twisted personal relationship."

Reyes-Alfaro, who is charged with three counts of murder and weapons violations and was being held in the Prince William County jail, entered the country illegally in February 2001, according to Immigration and Customs Enforcement officials. He was ordered deported in 2002 but later obtained an "immigration benefit" that allowed him to stay in the United States legally. That benefit was revoked in 2006.

Court papers say that Reyes-Alfaro has a child in El Salvador and that he told a neighbor he was in the military in his home country. Ashcraft and Reyes-Alfaro had dated for about eight years, said Joseph Belle, Ashcraft's husband, who had remained friendly with his wife even though they no longer lived together.

Ashcraft and Reyes-Alfaro, who rented a room in her townhouse, had recently broken off their romantic relationship, police officials said.

Just over an hour before the attacks, William Ashcraft, Brenda Ashcraft's 37-year-old son, told a supervisor at his job at RailPlan International that he was worried about his mother and asked to leave, RailPlan President Terry Soesbee said. The company performs maintenance for Virginia Railway Express.

"He said to his supervisor, 'My mom called me, and there is some big concern about her safety and I want to leave to make sure she is okay,' " Soesbee said. "That was the last direct contact we had with him."

On Friday, police were still piecing events together but said they were called to Ashcraft's home about 7:15 p.m. Thursday and found a gruesome scene. Brenda Ashcraft was dead in the front yard, and William Ashcraft, who had been shot in the chest, was inside the home, dying.

Two other people who lived there - a 15-year-old Osbourn High School student and a 34-year-old woman - were shot. The woman remained in the hospital Friday, and the teenager was released.

About 7:45 p.m., just a half-hour after the first attack, police were called to a home blocks away, where Reyes-Alfaro's friend, Ulloa, rented a room. Ulloa had been shot in the head.

Witnesses provided a description of Reyes-Alfaro's van, police said, and officers put out an alert. He was stopped by Prince William County police about 8 p.m. Police seized a machete, a gun, a cellphone and other evidence, court records show.

Rosa Gonzalez, 52, who lives next door to the Ashcrafts, said Reyes-Alfaro was friendly to her and would drive her to the supermarket when she needed groceries.

She said Reyes-Alfaro told her that he was in the military in El Salvador, where he has a wife and children. He once mentioned carrying a machete for protection.

"This is bad and scary, especially since he used to talk to me," Gonzalez said.

In March 2004, Reyes-Alfaro was arrested in Manassas for misdemeanor assault. According to court papers, Reyes-Alfaro told an officer he hit the victim in the head with a hammer because the man was "talking about him."

On April 8, 2004, he was found guilty of the charge and given a 90-day jail sentence, with all the time suspended.

On Jan. 25, 2008, Reyes-Alfaro was charged with drinking in public.

The shooting spree shocked neighbors in Manassas's Georgetown South neighborhood, which was built in the 1960s and has become rundown.

Last year, a 15-year-old student was killed there walking home from school. Manassas officials have spent the past few years doing cleanups and neighborhood safety programs to revitalize the community.

Brandon Paguadas, 18, said the Ashcrafts were very laid back and friendly.

"We kicked it sometimes in the summer," Paguadas said, noting that he walks by their house on his way to school. "They were the kind of people to always say 'Hi' or ask how you were when you walked by."

Joseph Belle said that Brenda Ashcraft loved dancing and partying and was a devoted mother who doted on her children.

"She was a very flamboyant lady," Belle said. "Manassas is a worse place without her. I don't know how you stop something like this. You don't know what goes through someone's mind."

glodm@washpost.com, buskej@washpost.com, whitejs@washpost.com Staff writer Tom Jackman and staff researcher Magda Jean-Louis contributed to this report.