Police Search Drew Peterson's Cars

Authorities executed another search warrant late Tuesday in the case of a former suburban Chicago police sergeant suspected in his 23-year-old wife's disappearance.

The latest warrant dealt with items inside two vehicles already seized from Drew Peterson's home, said Charles Pelkie, a spokesman for the Will County state's attorney's office. He declined to elaborate.

Peterson's attorney, Joel Brodsky, told WFLD-TV that the warrant says police are seeking items that "may have been utilized in commission of the offense of first-degree murder or the concealment of a homicidal death."

The warrant also indicates interest in trace elements of several materials, including blue plastic, Brodsky told the Fox affiliate.

Brodsky did not immediately return messages from The Associated Press.

A relative of Peterson's reportedly helped him move a heavy container out of his home and put it the family's sport-utility vehicle the day his wife vanished, an allegation Brodsky denied last week. A nonprofit group helping to search for Stacy Peterson has said police asked them to look for a blue plastic barrel large enough to hide a body.

Illinois State Police dive teams are searching the waters at the intersection of two canals in Lockport.

Three boats with divers on them were on the canal amid blowing snow and wind Wednesday.

A tow truck and police vehicles were alongside the canal, and divers appeared to try to hook a tow line from the truck to something in the water.

Irv Miller, legal analyst for CBS News station WBBM-TV says that even though a body is not necessary for a murder case, it's unlikely investigators will stop up looking for one. But in the case of Stacy Peterson, if she is dead, they may be running out of time.

"Winter is approaching, and that's going to make it really difficult to try to find a body," Miller said.

Illinois State Police did not immediately return a message left after business hours Tuesday.

After 23-year-old Stacy Peterson, the officer's fourth wife, disappeared in late October, authorities named her 53-year-old husband a suspect in what they have said is a potential homicide.

Prosecutors also are reviewing the death of Peterson's third wife, Kathleen Savio, and have said the drowning, deemed accidental at the time, may have been a homicide staged to look that way.

Peterson has not been named a suspect in her death.

"With all the hoopla, it's hard to believe something won't happen," he told WFLD-TV on Tuesday night.

On Nov. 1, state police seized two vehicles at the home the Petersons shared with their children - a GMC Denali and a Pontiac Grand Prix.

The vehicles were loaded onto trucks and taken to an undisclosed location.