In the world of cybersecurity, Juanita Koilpillai was at the forefront, working with the federal government to create impenetrable defenses against hackers and ransomware. She was a gifted programmer, visionary leader and one of the few women executives in the field, who willingly shared what she knew with the next generation, who she guided and mentored.

Her killing last week pierced many in the small and tightly knit security industry in which the 58-year-old worked. An associate said her death was a blow to national security because of her expertise in defining and understanding how to make virtual work environments secure. The manner in which police said she was killed made her loss even more unsettling, her friends said.

Police have arrested her son, 23-year-old Andrew Weylin Beavers, on suspicion of first- and second-degree murder in Koilpillai’s killing at their home in Tracys Landing last week, Anne Arundel County police said.

“The turn of events is so tragic,” longtime friend Ron Martin said.

Detectives said Beavers fatally stabbed Koilpillai sometime before the afternoon of July 25 at their home in the 6300 block of Genoa Road, hid her body and then fled in her car to Leesburg, Va. Officers from Anne Arundel and Loudoun counties arrested him Saturday in Leesburg after forensics tests showed his blood on the suspected murder weapon, police said.

According to Anne Arundel County police, Koilpillai’s boyfriend had reported her missing. He had come to her home on July 25 and called police, saying there was apparent blood inside and that Koilpillai could not be found.

Officers searched the house before finding her body outside. She had suffered apparent trauma and was pronounced dead at the scene, police said. Detectives noticed her car was missing.

An autopsy the next day determined that she had died as a result of multiple sharp force injuries, police said. The killing was planned and not a random attack, police said.

During their investigation, which included interviews with witnesses, detectives zeroed in on Beavers. Police said they found him and Koilpillai’s car in Leesburg on July 26. Police said he had a fresh cut on his right hand and would not explain how he had gotten it.

Among recovered evidence, police said they had seized what appeared to be the murder weapon. Anne Arundel County Forensic Services tested the weapon, and on Friday, results came back indicating that Koilpillai and her son’s DNA were on the edge of the weapon.

Police obtained an arrest warrant for Beavers on the same day and took him into custody without incident on Saturday at a home in the 39000 block of Thomas Mill Road in Leesburg. He taken into custody by the Loudoun County Sheriff’s Office pending extradition to Anne Arundel County, police said.

It is not clear whether Beavers has an attorney. Maryland court records do not list one for him. Two family members reached declined to comment.

Martin, a professor at Capital Technology University, has known Koilpillai since the late 2000s when she worked at a cybersecurity firm and he worked in the federal government. Over the years, they struck up a close professional friendship and shared a desire to educate and guide college students in the field.

“She was always willing to help out students,” Martin said. “I would always refer students to her that were in the cyber realm, and she would give them guidance and counsel.”

Born in Sri Lanka, Koilpillai was one of the few women programmers in the cybersecurity field in the 1990s that was dominated by young, brash and sometimes immature men who had grown up in the hacking world, said Jim Reavis, co-founder and chief executive of the Cloud Security Alliance.

“She was kind of an anomaly as this woman leader of a cybersecurity company,” Reavis said. “And she was one of the few that was sort of inventing the security management technology space.”

Reavis said Koilpillai’s companies were among the first to organize the different types of data being churned out by new cybersecurity services that surfaced over the past few decades and make it usable and understandable for security analysts.

“She was a pioneer and an early advocate of cloud computing and the need to secure that,” he said.

She held the title of founder and chief executive at Resiliant, an offshoot of Waverly Labs, which she also helped found and lead. Resiliant creates secure “zero trust” parameters online for organizations to operate their computer systems that are supposed to be impenetrable and undetectable to hackers, according Resiliant’s website. The federal government was one of their clients, her friends said.

She was skilled working with people as a manager and networker who made introductions and inroads between cybersecurity experts and the federal government. As a programmer, she was especially good at thinking about how to secure virtual office operations at a time when the pandemic made such remote work crucial.

“That was an area she was leading for, and she has for several years, and that’s where we all need to go,” Reavis said. “It’s not only a personal loss I’m feeling, but I think it’s a real sort of national security loss for our country.

During one of Reavis’s last interactions with Koilpillai, he said, she had met several people working in the Alliance and impressed many with how easily she rattled off what they did as if she knew them.

She was the type who took time to learn about others she interacted with, Reavis said.

Police continue to investigate Koilpillai’s homicide and ask anyone with information to contact the Anne Arundel County Homicide Unit at 410-222-4731 or anonymously through a tip line 410-222-4700 or Metro Crime Stoppers at 866-7LOCKUP, the P3Tips app on mobile phones or online at www.metrocrimestoppers.org.

Researcher Jennifer Jenkins contributed to this story.