NASHUA, N.H. (CBS/AP) – The trial of a New Hampshire man charged with killing a 42-year-old Mont Vernon woman in her home last year resumed Monday with testimony from an undercover detective who helped recover key evidence.

Prosecutors have asked that the image and voice of New Hampshire State Police Detective Steven Tarr not be made public for his own safety.

Tarr is testifying that he accompanied a co-defendant to recover vital evidence from the Nashua River.

18-year-old Steven Spader of Brookline is on trial for murder and other charges for the Oct. 4, 2009, attack that killed Kimberly Cates and injured Cates’ 11-year-old daughter Jaimie.

Last week witnesses testified Spader attacked the Cates’ with a machete.

On Monday, jurors were shown items that link Spader and co-defendant Christopher Gribble to items taken from the home.

The detective held up a sweatshirt bearing Spader’s name and socks and a towel with Gribble’s name.

The items were in a garbage bag retrieved from the river.

Police also found in the river a wallet containing multiple identification cards for Kimberly Cates’ husband David, who was traveling during the attacks.

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