Crews in Linden, Calif. were continuing to search for the remains of victims of the Speed Freak Killers Monday.

Crews were digging by hand in an area one of the killers said was the wrong place.  So far, no remains have been recovered, but workers have a long way to go.

The FBI is digging at an abandoned well in Linden based, in part, on information from death row inmate Wesley Shermantine.

But Shermantine in a letter claims investigators are digging in the wrong place.

"I see what you guys are doing," he said in his letter. "You planned to come up empty handed the whole time, this way you can claim my information is no good."

Private investigator Rob Dick spoke with Shermantine by phone Monday morning.

"He's adamant that he never went or pointed out to where they're digging right now and just cannot understand why they're digging in that location," Dicks said.

Shermantine led investigators to a well last year that yielded the skeletal remains of four women.

It's believed that Shermantine and Lauren Herzog killed dozens of people in the 1990s.

The FBI said on Thursday it started the hand-digging operation using a crane to lower personnel in a basket into the well.

The question remains: Will the FBI find bones at the bottom of this well?

"Bottom line is whether they do or they don't, I would hope that they keep to their word to move on to these next locations so we can rule them in or out," Dick said.

The FBI said Shermantine's recollections have, at times, proved to be inaccurate. The organization believes this well offers the best chance to find remains.

It's expected the digging the well by hand will take weeks.