PHOENIX - When Romelia Vargas was gunned down in the catering truck where she fried taquitos, police had few answers for her husband. Maybe the mother of twin baby boys got into trouble selling drugs - that was the best they could offer.
Alvin Hogue never accepted that explanation, but when a detective called months later with a better one, he was so stunned he had to pull his cement truck over to the side of the road.
Vargas and her cook, Mirna Palma-Roman, were victims of the Baseline Killer, a serial predator who police say has killed eight people and sexually assaulted 11 other women and girls in the Phoenix area in just over a year.
His targets have been random and vulnerable, like the two women working alone one February morning near a construction site.
"I was in disbelief," Hogue said in an interview at his home this month while his 9-month-old twin sons wiggled and whined at his feet. "I'll be so happy when they catch him."
After arresting two suspects in another serial killing case this month, authorities have ramped up their efforts to find the Baseline Killer, named for the south Phoenix road near where the earliest crimes occurred. The investigation is revisiting hundreds of unsolved cases in hopes of tracking the man down.
Police will not discuss their lab work, but say they have tried to connect cold cases to those already linked to the Baseline Killer using state and federal forensic databases.
"We have a whole room dedicated to the task force, replete with computers and investigators and analysts," said Sgt. Andy Hill, a spokesman for Phoenix police. "There's a lot of leads from the past we've had. There's a lot of leads that are coming in" through anonymous tips.
Although the search has not netted the Baseline Killer, it has provided some answers for victims' families and shed light on other investigations.
In one case, Phoenix investigators linked the Baseline Killer to a killing in nearby Tempe that had been blamed on another man.
Police say they are still getting a high volume of calls from tipsters, despite the focus on the Aug. 3 arrests of suspects in Phoenix's other serial-killings case - the Serial Shooter case. Samuel John Dieteman, 30, and Dale S. Hausner, 33, pleaded not guilty Monday to two counts of murder and 14 counts of attempted murder in that case.
The Baseline Killer's most recent attack was nearly two months ago, when police say he carjacked 37-year-old Carmen Miranda at a car wash and later killed her.
"There's a possibility that the suspect could have moved to a different area," Hill said.
TV stations continue to broadcast a police sketch of what the Baseline Killer might look like, though investigators say they still do not really know.
He is thought to wear disguises, changing hats and the length of his hair. He strikes quickly, in the dark, and generally targets people who are alone.
Police say they have no suspects.
"It's got to be a person who's in a lot of pain," Hogue said. "For him to do something so heinous, to go around killing people so indiscriminately, the best thing for him to do is turn himself in and get some help."
Hogue said he's trying to move on. He's hired a nanny for his sons, and the lunch wagon is back on the street. But when Vargas was alive, the business had been doing so well the couple had planned to convert another truck and start a franchise.
"You know the person who took her life? They took potentially 50 years from my wife," Hogue said. "The joys from her life. Her kids, her family, to watch her kids grow up, kids, grandkids."