Prosecutors in Scott Peterson's (search) murder trial sought Tuesday to counter defense claims that police were so eager to charge their client with his wife's killing that they ignored other credible tips.

Two investigators testified that in the weeks after Laci Peterson (search) vanished they pursued a tip that the pregnant schoolteacher was held in a rural area about 30 miles from her hometown.

Modesto police officer Eric Beffa (search) testified about an anonymous tip received in early January 2003, weeks after the disappearance, that Peterson was being held captive near the suburb of Tracy.

Beffa quoted from a report: "They have a pregnant woman there and he states he recognizes her to be Laci. ... He doesn't want the reward money; he just wants her to be found."

He and a San Joaquin County sheriff's deputy, Paul Mears, testified that they and other law enforcement personnel responded to the area but were unable to find any sign of the woman, despite a four-day search.

Prosecutors allege Peterson killed his wife in their Modesto home on or around Dec. 24, 2002, then drove to San Francisco Bay and dumped her body. The remains of Laci Peterson and the couple's fetus washed ashore in April 2003, not far from where Peterson set out for what he claims was a solo fishing trip that Christmas Eve morning.

Defense lawyers contend someone else abducted and killed Laci, then framed their client after learning of his widely publicized alibi.

As the trial entered its 15th week, prosecutors prepared to introduce evidence they say places Laci Peterson on the boat police allege Scott Peterson used to dispose of her body.

A pair of pliers found on the boat contained a strand of hair that prosecutors claim DNA testing indicates likely came from Laci Peterson.

It's their only piece of potential physical evidence linking Laci to the boat police claim she never knew her husband had purchased.

Sarah Yoshida, a state criminalist, testified Tuesday that she found no signs of blood or tissue on two pairs of Peterson's pliers seized by police. Under cross-examination, she said the pliers were rusty and showed no signs of recent use.

Outside court, Peterson's parents and Laci's parents appeared to have the first verbal confrontation of the trial.

Laci's stepfather, Ron Grantski, has spoken out previously about how ridiculous it is that Peterson went fishing on Christmas Eve, when Grantski himself would later testify that he, too, went fishing alone that morning.

"Where did you go fishing?" Peterson's father, Lee, said to Grantski on Tuesday as the families left the courtroom.

"You come down here and I'll tell you where I went fishing," Grantski replied sternly, heading down the courthouse escalator.