Tonya Brown is leading a group of citizens in a search party for her brother, 25-year-old Max Greenfield of Harbor, who was last seen March 18 at the Lucky 7 Casino in Smith River.

The endeavor begins at 11 a.m. at the former Ray’s Market parking lot in Smith River. Brown hopes to cover the beaches north from the mouth of the Smith River, Kellogg Beach, Ocean View Drive and California 197.

“I worry he’s in the ocean,” Brown said. “At this point, we just need answers.”

Del Norte County is investigating the case and began a search with dogs Tuesday evening, to no avail, Brown said.

Video surveillance shows Greenfield walking into the Lucky 7 Casino in Smith River at 1 a.m. March 18, then walking outside and waiting near the casino’s backdoor. At 1:50 a.m., he was seen walking around to the front of the casino, where he met with a white adult male, with whom he spoke for several minutes.

The two were then seen walking south across the parking lot adjacent to U.S. 101, until they walked out of the camera’s range. That man was later identified and questioned by law enforcement, and said he’d walked down the highway with Greenfield, but turned around and returned to the casino, said Curry County Sheriff John Ward.

“This entire situation is an absolute nightmare,” Brown said. “I’ve never searched for a person before. Curry County, as well as Del Norte, have been very helpful. They are actively searching the Smith River area. My family is going through hell trying to find him. He has never been gone more than 30 hours without contacting us. We fear the worst.”

The investigation into Greenfield’s disappearance is being conducted by Del Norte County Sheriff’s Office, although officials from the U.S. Department of Justice’s National Missing and Unidentified Persons System called Curry County asking to list Greenfield on their website.

Greenfield is a white male, about 6 feet tall, weighing 150 to 160 pounds, with brown hair, green eyes and a skeleton key tattoo on his left forearm. At the time of his disappearance, Greenfield was wearing black jeans and jacket, a dark T-shirt and knit stocking cap and carrying a black duffel bag.

Anyone with information is asked to call the Del Norte County Sheriff’s Office at 707-464-4191 or the Curry County Sheriff’s Office at 541-247-3242.