But as officers conducted their investigation, they made a grisly discovery: mummified human remains, apparently used for religious rituals, inside one of the closets.

The man who lived in the home, Robert F. Williams, 53, was arrested Thursday and charged with second-degree desecration of human remains, for which he could face up to 10 years in prison, officials said.

He was also charged with numerous counts in the sexual abuse case, including aggravated sexual assault, endangering the welfare of a child and luring.

As of Tuesday morning, Williams remained in custody, according to jail records. It was unclear whether he had a lawyer, and the state public defender’s office did not respond to requests for comment.

Williams’ block in Newark’s West Ward section was quiet Monday, but there was a strong smell that neighbors said they had noticed for weeks.

None of them were sure of its source, but Williams’ arrest led them to speculate that the smell may have been linked to the remains. Officials said they did not have evidence that the smell was connected to Williams.

Sarah Douglas, 66, who lives nearby, said: “I was trying to find a logic for that, but a dead body is a dead body.”

The odor “lit up the whole street,” she said.

The smell grew stronger closer to Williams’ apartment, on the first floor of a light-blue, three-family house. Douglas said the odor coming out of Williams’ home was hard to ignore, even when she closed her windows to hinder it.

“That smell there. It was real ripe,” Douglas said. “The minute you opened that door, it was there.”

Williams’ upstairs neighbor, Hakeema Christopher, said she had caught a whiff of the odor as early as July. When she complained about the stench, she said, Williams responded by giving her cleaning supplies and a sponge.

Newark police began investigating Williams for sexual abuse after receiving a call from the 13-year-old boy’s father, a police official said Monday. The abuse began last year, prosecutors said, and involved multiple encounters over several months.

Officers at the apartment Monday were shocked by the gruesome discovery of the remains, the official said, and dogs were called in to sniff out other remains. In addition to a plastic bin with the mummified remains, police also found a spine with an intact rib cage and a bag of bones, all of which were believed to belong to the same corpse.

Officials were not sure to whom the remains belonged or from where they came. The regional medical examiner’s office was investigating them, hoping to determine more information about their origin, said Katherine Carter, a spokeswoman for the Essex County prosecutor’s office.

The remains were not believed to be directly linked to the sexual abuse, officials said. Williams told detectives that he purchased them and used them for religious rituals, the police official said. In addition to the human remains, officers found an altar “to an unknown deity” in Williams’ bedroom.

On Monday, several neighbors and acquaintances said they were not aware of Williams’ religious activities.

Vanessa McClees, who briefly lived in Williams’ building, said that when she saw Williams last Wednesday, the day before his arrest, he was wearing about a dozen beaded necklaces.

When she inquired about them, he told her that it was part of his “religious thing,” McClees said.

As a neighbor, Williams appeared “cool” in the beginning, Christopher said. But she said that when she and her family moved to the floor above Williams in June, the previous residents of the apartment warned her to keep an eye on her children.

“They told me that he liked kids and to keep my distance from him,” Christopher, 24, said.

McClees also said that Williams was known for taking neighborhood children to the store or a nearby pancake house but that she did not think anything of it at the time.

Douglas said that she would sometimes spot Williams with children around 12 or 13 years old. He would refer to the children as his nieces and nephews, she added.

She said Williams would tell her: “When my nieces and nephews come over, I keep them in the house. I don’t let them come out. You have got to be so careful with your children because you never know.”

On Monday, the hallway leading to Williams’ apartment was covered with old garbage, including fifth- and seventh-grade math workbooks that Christopher said he had placed there weeks earlier.

Recently, Christopher said, she saw red flags that suggested he was hiding something.

About two weeks ago, Christopher said, she knocked on his door and asked to borrow a hammer to install curtains. Williams answered and appeared agitated.

She recalled him saying, “Oh, I’m really busy right now. This is not a good time. I’ll give it to you tomorrow.”

In 2002, the Newark area faced a series of cemetery and mausoleum robberies that police said were possibly part of religious rituals. In one case, a man and his son were found to have a cauldron of stolen bones that officials believed was connected to Palo Mayombe, an African-Caribbean religion linked to Santeria.

The spate of grave robberies prompted New Jersey lawmakers that year to increase the penalty for digging up graves or otherwise stealing human remains.

This article originally appeared in The New York Times.