Drew Peterson under arrest

Reported by: Jay Gray
NBC

Former police officer Drew Peterson has been the primary suspect in the murder of his third wife Kathleen Savio and disappearance of his fourth wife Stacey.

Both cases have drawn national attention.

But no arrests took place until late yesterday.

That's when Peterson was taken into custody at a traffic stop about a mile from his suburban Chicago home.

He will be arraigned this afternoon on a charge of murder in the Savio case.

The brash former police sergeant, making light of the situation, reportedly told arresting officers, "I guess I should have returned those library books."

"We're very confident in our case," said Will County State's Attorney James Glasgow.

Initially, investigators determined Savio's death was an accidental drowning after she was found dead in her bath tub five years ago.

But in October of 2007, when Peterson was named by police as the primary suspect in the disappearance of fourth wife Stacey, officers decided to take a closer look at the Savio case.

Her body was exhumed, and after a forensic examination her death was reclassified as a homicide.

"Our journey has been far and wide, it has been exhausting," says Illinois State Police Capt. Carl Dobrich.

Armed with a new search warrant, officers recovered more evidence from Peterson's home late Thursday.

A former police officer, Peterson retired after Stacey disappeared.

He has never shied from the spotlight, or controversy, surrounding the cases involving his former wives.

And he's continued to maintain his innocence.

"I can look you right in your eye and say I had nothing to do with either of those incidents," Peterson once told an interviewer.

It appears now that Peterson will get that opportunity in court.

Something the Savio family has been waiting for since her death.

"We're hoping that this will be the justice that we always wanted, knew that we could have, hopefully my sister can rest in peace," says Nick Savio, Kathleen's brother.

Peterson remains in custody today, his bond has been set at $20 million.

His attorneys will argue today that the judge should require a lower bond amount.