A 25-year-old man has been charged with murder after authorities say he randomly stabbed a woman to death in a quiet South Florida neighborhood, according to the Martin County Sheriff’s Office.

Kersten Francilus, who lives in a nearby community, is accused of attacking a woman in her 70s as she walked her dog Friday in the Southwood neighborhood in Stuart, Sheriff John Budensiek said.

Neighbors had called deputies shortly before the attack to report a suspicious man going door to door and asking unusual questions.

“We receive multiple calls in this community. The Southwood community, which is a quiet, higher end community here in Martin County. Multiple calls of a suspicious male walking door to door and interacting with different people,” Budensiek said during a news conference.

Mugshot of Kersten Francilus with a thin object protruding from his right cheek.
Kersten Francilus, 25, has been charged with murder after allegedly stabbing a woman to death in Southwood, Florida.Martin County Sheriff’s Office/Facebook
“He asked several times, several different people where the new bank was. There’s no bank around here,” he said.

Witnesses described the man as calm and nonconfrontational during those encounters, the sheriff said.

A short time later, authorities received additional calls reporting that the same man was attacking a woman in a cul-de-sac.

Four police officers, two wearing "Sheriff" uniform shirts, discussing a situation outdoors.
The Martin County Sheriff’s Office investigates the murder in Southwood.Martin County Sheriff’s Office/Facebook
A deputy who was already en route to investigate the suspicious activity arrived to find the suspect “actively stabbing” the victim while she lay on the ground, Budensiek said.

“Our suspect was on top of her, actually actively stabbing her,” he said.

A brave Good Samaritan attempted to intervene but was unable to stop the attack before deputies arrived, officials said.

Martin County Sheriff's vehicles and yellow crime scene tape at an investigation site.
Witnesses described Francilus as calm and nonconfrontational, the sheriff said.Martin County Sheriff’s Office/Facebook
When confronted by the deputy, Francilus immediately dropped the knife and surrendered.

The victim suffered stab wounds to the upper torso and was transported to Cleveland Clinic Martin South, where she died, authorities said.

“This was a violent, vile homicide,” Budensiek said.

Police said there is no known connection between Francilus and the victim, and no clear motive has been identified.

“At this point, this appears like an extremely violent, random act of violence,” Budensiek said.

A police officer in a tactical vest wraps yellow police tape around a wooden post.
The victim, in her 70s, was out walking her dog when Francilus brutally attacked her.Martin County Sheriff’s Office/Facebook
Francilus was taken into custody at the scene and later booked into the Martin County Jail. Authorities said the knife used in the attack was a steak knife believed to have come from his home.

The sheriff’s office said Francilus has no known criminal history, though deputies had previously responded to a call involving him acting strangely at his residence.

Budensiek said residents were wise to report the man’s peculiar behavior.

“The community did what they needed to do. They saw something that wasn’t right. They called the Martin County Sheriff’s Office,” he said.

Authorities have not released the victim’s name.