LINDEN -- The FBI returned to Linden on Tuesday with shovels and investigation crews as yet another site connected to convicted serial killer Wesley Shermantine was surveyed.

The site, along Flood Road, was blocked off by San Joaquin County Sheriff's Office deputies as the FBI spent the morning and part of the afternoon inspecting the area.

FBI spokeswoman Gina Swankie said the area was being surveyed for a possible dig for remains from the killing spree of Shermantine and his partner-in-crime, Loren Herzog.

But she cautioned that the FBI's presence doesn't necessarily indicate anything is imminent.

"It doesn't mean we are going to start a dig tomorrow," Swankie said.

The sheriff's office would not comment on the dig.

The site surveyed is off Flood Road, as was a different site where the FBI brought Shermantine in August to point out possible burial locations.

Herzog and Shermantine were convicted of four murders and suspected in the deaths of as many as 15 people in and around San Joaquin County from 1994 to 1998. They were arrested in 1999. The pair were nicknamed "The Speed Freak Killers" due to their methamphetamine addiction.

The last time crews were out in Linden was Aug. 26, when Shermantine, under heavy guard, was escorted from San Quentin State Prison to the barren land that he said was the burial site for his and Herzog's victims.

Shermantine is on death row for four murders. Herzog committed suicide in January at his trailer in Lassen County, hours after being told that Shermantine was cooperating with authorities.

Contact Katie Nelson at 925-847-2164 or follow her at Twitter.com/katienelson210.