Environmental engineer Tim Nelligan, center, performs soil vapor testing in the front yard of the property next door to Susan Flores’ home on East Branch Street in Arroyo Grande as part of the Kristin Smart investigation on May 6, 2026. Susan Flores is the mother of Paul Flores, who was convicted of Smart’s murder in 2022.
Environmental engineer Tim Nelligan, center, performs soil vapor testing in the front yard of the property next door to Susan Flores’ home on East Branch Street in Arroyo Grande as part of the Kristin Smart investigation on May 6, 2026. Susan Flores is the mother of Paul Flores, who was convicted of Smart’s murder in 2022. Credit: Joan Lynch / San Luis Obispo Tribune photo

The search of the Arroyo Grande home of convicted killer Paul Flores’ mother continued on Thursday as part of ongoing investigation into the Kristin Smart case.

Paul Flores was convicted in 2022 of killing Smart when she was a first-year student at Cal Poly. Smart went missing nearly 30 years ago on Memorial Day weekend of 1996. Her body has never been recovered.

On Wednesday, the San Luis Obispo County Sheriff’s Office served a search warrant at 529 Branch St., the home of Susan Flores.

Throughout the day, law enforcement could be seen entering and exiting the home, as well as a neighboring property’s yard, as people appeared to take samples of soil. The search was expected to continue into Thursday, according to the Sheriff’s Office.

In a news release Wednesday, the San Luis Obispo County Sheriff’s Office said it was conducting an investigation into the property in the 500 block of East Branch Street in Arroyo Grande.

The investigation was “the result of a search warrant signed by a Superior Court judge,” the release said. “The Sheriff’s Office remains committed to bringing Kristin home to her family,” the release said.

Denise Smart, Kristin Smart’s mother, has previously said that the case will not be over for the family until her daughter’s remains are found and returned home.

“There’s no finality for us,” she told The Tribune in January following Paul Flores’ final appeal being denied.

The Smart family has not issued a statement about the latest search as of Thursday morning.

San Luis Obispo County Sheriff’s Office Det. Clint Cole speaks to others outside an Arroyo Grande home on Wednesday as a search warrant was served in the Kristin Smart investigation. The home belongs to Susan Flores, the mother of Paul Flores, who was convicted of Smart’s murder in 2022.
San Luis Obispo County Sheriff’s Office Det. Clint Cole speaks to others outside an Arroyo Grande home on Wednesday as a search warrant was served in the Kristin Smart investigation. The home belongs to Susan Flores, the mother of Paul Flores, who was convicted of Smart’s murder in 2022. Credit: Joan Lynch / San Luis Obispo Tribune photo

In recent years, Susan Flores’ Arroyo Grande home has become a prominent point of interest in the push to find Kristin Smart’s remains — especially after a group of scientists in 2023 announced a soil vapor sampling study saying they had discovered evidence of a “human decomposition event” emitting from the property’s yard.

On Wednesday, a soil vapor probe for vapor intrusion testing could at one point be seen plugged in front of a home near the Flores property and a group of people including environmental engineer Tim Nelligan could be seen conducting sampling tests of the soil.

Susan Flores has never been charged with a crime associated with the Kristin Smart case.

The Sheriff’s Office has not released specific information on the extent of this week’s search, nor on what investigation activities are ongoing at the site.

On Thursday, much of the scene appeared quiet, with a few Sheriff’s Office investigators walking to the home.

SLO Tribune reporters Chloe Schrager and Hannah Poukish contributed reporting to this story.

This is a developing story. Check back to sanluisobispo.com for updates.