MIDLAND CITY, Ala. -- As a police standoff with an Alabama man accused of holding a 5-year-old boy hostage in an underground bunker entered its fifth day, authorities were saying little except that their talks with the 65-year-old loner were continuing through a ventilation pipe.

Negotiators were still trying Saturday to persuade Jimmy Lee Dykes to surrender. Police have said they believe the Vietnam-era veteran fatally shot a school bus driver Tuesday, and then abducted the boy from the bus and disappeared into the home-made bunker.

While police were mostly staying mum about the delicate negotiations, it fell to neighbors to fill in the blanks about Dykes, described by some as a menacing figure with anti-government views.

One of Dykes' next-door neighbors said the suspect spent two or three months constructing the bunker, digging several feet into the ground and then building a structure of lumber and plywood, which he covered with sand and dirt.

Neighbor Michael Creel said Dykes put the plastic pipe underground from the bunker to the end of his driveway so he could hear if anyone drove up to his gate. When Dykes finished the shelter a year or so ago, he invited Creel to see it - and he did.

"He was bragging about it. He said, 'Come check it out," Creel said.

He said he believes Dykes' goal with the standoff is to publicize his political beliefs.

"I believe he wants to rant and rave about politics and government," Creel said. "He's very concerned about his property. He doesn't want his stuff messed with."

Police have used a ventilation pipe to the bunker to talk to the man and deliver the boy medication for his emotional disorders, but they have not revealed how often they are in touch or what the conversations have been about. Authorities waited until Friday to confirm the suspect's identity.

While much of what is going on inside the bunker remains a mystery, local officials who have spoken to police or the boy's family have described a small room with food, electricity and a TV. And while the boy has his medication, an official also said he has been crying for his parents.

Meanwhile, Midland City residents held out hope that the standoff would end safely and mourned for the slain bus driver and his family. Candlelight vigils have been held nightly at a gazebo in front of City Hall. Residents prayed, sang songs such as "Amazing Grace" and nailed homemade wooden crosses on the gazebo's railings alongside signs that read: "We are praying for you."

"We're doing any little thing that helps show support for him," said 15-year-old Taylor Edwards said.

Former hostage negotiators said authorities must be cautious and patient as long as they are confident that the boy is unharmed. Ex-FBI hostage negotiator Clint Van Zandt advised against any drastic measures such as cutting the electricity or putting sleeping gas inside the bunker because it could agitate Dykes.

The negotiator should try to ease Dykes' anxieties over what will happen when the standoff ends, and refer to both the boy and Dykes by their first names, he said.

"I want to give him a reason to come out," Van Zandt said.

State Rep. Mike Ball of Huntsville, who spent 15 years as a hostage negotiator with the Alabama Bureau of Investigation, said Saturday that the key is patiently building a relationship with Dykes.

"They want to build a relationship with him and calm down the feeling of hopelessness he has," he said. "Any day that goes by with the child alive is a victory. If you string enough of those days together, he will come out."

At a brief news conference Friday to release a photo of Dykes, police brushed off any questions about possible charges.

"It's way too early for that," said Kevin Cook, a spokesman for the Alabama state troopers.

Police have described the bunker as about 4 feet underground, with about 6-by-8 feet of floor space and the PVC pipe that negotiators were speaking through.

State Rep. Steve Clouse, who represents the Midland City area, said he visited the boy's mother and she is "hanging on by a thread." Clouse said the mother told him that the boy has Asperger's syndrome as well as attention deficit hyperactivity disorder, or ADHD.

Dr. Nadine Kaslow, a family therapist and psychiatry professor at Emory University in Atlanta, said the boy's emotional troubles might make things even more difficult for him.

"They have less way to make sense of things," she said of children with Asperger's and ADHD.

The normally quiet red-clay road leading to the bunker was busy Friday with more than a dozen police cars and trucks, a fire truck, a helicopter, officers from multiple agencies and news media near Midland City. The town, population 2,300, is about 100 miles southeast of Montgomery.

Police vehicles have come and gone for hours from the command post, a small church nearby.

Neighbors said Dykes was easily angered and once beat a dog to death with a lead pipe, threatened to shoot children for setting foot on his property and patrolled his yard at night with a flashlight and a firearm.

He was in the Navy from 1964 to 1969, serving some time in Japan, according to military records.

Authorities said Dykes boarded a stopped school bus filled with 21 children on Tuesday afternoon and demanded two boys between 6 and 8 years old. When the driver tried to block his way, the gunman shot him several times and took the 5-year-old boy.

The bus driver, Charles Albert Poland Jr., 66, was hailed by local residents as a hero who gave his life to protect the pupils on his bus.

Dykes had been scheduled to appear in court Wednesday to answer charges he shot at his neighbors in a dispute last month over a speed bump. Neighbor Claudia Davis said he yelled and fired shots at her and her family over damage Dykes claimed their pickup truck did to a makeshift speed bump in the dirt road. No one was hurt.

Creel said his father and Dykes are friends. Creel said that after Dykes' arrest, Dykes wrote a 2- to 3-page letter that at least in part addressed the menacing case.

Michael Creel said he hasn't seen the letter but that his father, Greg Creel, has. Dykes reportedly told the elder Creel he had sent the letter to the local media, politicians and Alabama's governor.

Police on Friday took a copy of the letter from the Creels' home, according to Michael Creel. Reached for comment, Greg Creel confirmed the existence of the letter but declined further comment and said he was cooperating with police.

A neighbor directly across the street, Brock Parrish, said Dykes usually wore overalls and glasses and his posture was hunched-over. He said Dykes usually drove a run-down "creeper" van with some of the windows covered in aluminum foil.

Parrish often saw him digging in his yard, as if he were preparing to lay down a driveway or building foundation. He lived in a small camping trailer and patrolled his lawn at night, walking from corner to corner with a flashlight and a long gun. Authorities have not disclosed what firearms Dykes might have in his possession.