A 30-year-old man accused of killing his sister inside a Lynn, Massachusetts apartment Sunday was out on probation at the time of her death, according to prosecutors.

Joshua Smith was arraigned on Monday in Lynn District Court on charges of murder and kidnapping. A plea of not guilty was entered on his behalf.

Lynn murder arraignment

Both the prosecution and defense agreed that Smith be held without bail until a probable cause hearing on October 14.

Smith's sister, 38-year-old Michelle Knox, was found dead just after 1 a.m. Sunday when police responded to a call on Newhall Street. 

The prosecution said that Smith killed Knox at an apartment where he was staying with his father. No details about her death were revealed during Smith's arraignment.

Prosecutors said that when officers arrived at the apartment, Smith was outside "making numerous inculpatory statements about killing his sister."

The judge ruled that Smith violated his probation in a previous case. His defense attorney Michael Phelan spoke to reporters outside of court on Monday. Phelan did not comment on why Smith was on probation.

"He's been through the system before so he understands what's going to be happening," Phelan said.

The attorney said he was still learning details about the case and was not able to comment on what he believes happened to Knox. 

Neighbor describes police response

A man who has lived in the building for 10 years, who didn't know Smith or Knox, said police lights and commotion woke him up early Sunday.

"I heard the sirens and everything and then woke up and seen blue lights, I'm like, OK what's really going on? I got nervous and kind of put my stuff on, woke up, put some clothes on, and basically was trying to make sure everyone else was OK," Kenji Taylor said. "It's just the same thing, you know? It's Lynn, it happens."

Documents related to the case were ordered to be impounded. The judge ordered Smith to have no contact with several family members.