Scott Peterson's (search) trial resumed Monday with testimony from a Modesto police sergeant about numerous searches of San Francisco Bay in the weeks after the remains of Peterson's wife and fetus washed ashore.

Sgt. Rick Armendariz testified he was involved in water searches on several days in 2003, including May 10, May 16, May 17, May 18, Sept. 11 and Sept. 18.

Armendariz said authorities were seeking any evidence or partial remains that may be connected to the deaths of Laci Peterson (search) and her fetus. Laci's body — just a torso — and that of the fetus washed ashore in April of 2003, just two miles from where her husband, now charged in the deaths, claimed to have been fishing alone on the bay the day she was reported missing — Dec. 24, 2002.

"As far as you know you didn't find anything of evidentiary value, correct?" asked defense lawyer Mark Geragos (search).

"On the boats I was on, correct," Armendariz said.

The case resumed Monday following a four-day weekend — the beginning of its seventh week, one that could see the most-anticipated witness called to the stand.

Prosecutors are still making their case that Peterson killed his wife in their Modesto home on or around Dec. 24, 2002, trucked the body to San Francisco Bay in a large tool box and plunged it overboard from a small boat.

His alleged motive: an affair with massage therapist Amber Frey (search).

Frey, who began cooperating with authorities soon after Laci Peterson was reported missing, could testify this week. Though a judge has imposed a gag order, preventing attorneys from discussing who will be called, court officials recently advised media about special procedures for when Frey testifies.

It seemed she would be called last week as the culmination of testimony about how Peterson lied to authorities about his personal life — including a denial of the affair. Instead, prosecutors shifted course and showed pictures of the remains of Laci Peterson and the couple's fetus, which washed onto a shore near where Peterson said he was fishing on the day his wife was last seen.

Defense lawyers say someone else abducted Laci Peterson as she walked the dog and held her captive before dumping her body to frame her husband. Peterson, 31, could face the death penalty if convicted.