Philadelphia (CNN) -- A fourth person was arrested in the case of four mentally disabled people who were found locked in the boiler room of a Philadelphia apartment building over the weekend, police said Wednesday.
Jean McIntosh, 32, is charged with offenses including kidnapping, conspiracy, unlawful restraint, false imprisonment, aggravated assault, simple assault, burglary and trespass, the Philadelphia district attorney's office said in a statement.
McIntosh is the daughter of Linda Ann Weston, 51, one of three people previously arrested, the statement said. McIntosh is "accused as a co-conspirator in the kidnapping and imprisonment of the four individuals."
McIntosh was brought in for questioning Tuesday night and arrested early Wednesday, said Philadelphia police spokesman Officer Christine O'Brien. No bail had been set.
Jean McIntosh, 32, is charged with kidnapping, assault, burglary and other offenses.McIntosh was a tenant of the Philadelphia apartment building where the four were discovered, said the building's owner, Turgut Gozleveli, who found the captives, and block captain Danyell Tisdale, who alerted Gozleveli to suspicious activity.
"I'm feeling sick to my stomach," Tisdale told CNN Wednesday. "I was speaking so highly for her. She was a nice neighbor and didn't bother anybody. It's shocking to me that she had anything to do with it. My sister's children played with her two children."
McIntosh is expected to appear in court Wednesday, prosecutors said.
On Tuesday, Philadelphia police Commissioner Charles Ramsey said a woman rescued from the boiler room claims she had two children while being held against her will, and that authorities have located 10 other potential victims.
The four people, three men and a woman ranging in age from 29 to 41, were found locked in the room with no food and only a bucket for a toilet, police said. The pitch-black, 15-foot-by-6-foot space houses what police described as a boiler used to heat the building. A penetrating stench of urine and feces still hung in the chamber days after the discovery.
One of the four, identified as Derwin McLemire, had been chained to the boiler, police said.
While police have not released the names of the four alleged victims, they confirmed the accuracy of media reports identifying them as McLemire, Herbert Knowles, Edwin Sanabria and Tamara Breeden.
Linda Ann Weston, 51, had ID documents for about 50 people when arrested, Philadelphia's police commissioner said. Authorities initially identified Gregory Thomas, 47, as Thomas Gregory and later corrected the name. A preliminary hearing for Weston, Thomas and Eddie Wright, 49, on charges and evidence in the case will be October 24.Weston; Gregory Thomas, 47; and Eddie Wright, 49, were previously arrested. Authorities were investigating whether the victims' Social Security checks had been stolen, as well as several other leads.
Six of the 10 new alleged victims are children, Ramsey said. Two of them, ages 2 and 5, are believed to be the children born to Breeden, police said. Authorities did not divulge how Breeden became pregnant.
Another is a 19-year-old niece of Weston, Ramsey said.
"The 19-year-old has visible injuries, she may have been beaten, and she has scars all over her body," Ramsey said.
Breeden said while she was with Weston, "she says she gave birth to two children and we have no reason to doubt it," he said.
Weston had identification documents for about 50 people with her when she was arrested, Ramsey said. They included Social Security cards and court documents giving power of attorney, among others.
Ramsey said police must track down all of those individuals and find out what happened to them and whether they were victims. It is possible that Weston has been involved in similar activity dating back to the late 1990s, he said.
"We don't know the extent of this," Ramsey told CNN Tuesday. "We do know it goes beyond the borders of Pennsylvania -- at least Texas, Florida and Virginia, and we suspect other locations as well."
Three of the four alleged victims spoke to the media about their harrowing experience on Monday.
"That was real dirty of you. That was wrong," a tearful McLemire told CNN affiliate KYW, talking about his alleged captors.
The alleged victims said they were beaten and were afraid of the suspects in the case.
Breeden told KYW Weston hit her in the head, "and all this was bleeding and everything."
McLemire, Breeden and a third man, Herbert Knowles, told KYW their Social Security information was taken from them.
McLemire, who said he is from North Carolina, said he met Weston on an online dating site, according to KYW. He said once he attempted to escape from a home of Weston's, "and I didn't get away, so they got me."
Bond for each of the three suspects was set at $2.5 million, according to the Philadelphia district attorney's office. The FBI joined the probe after detectives discovered one of the accused had traveled to at least two other states with the people found in the basement of the northeast Philadelphia apartment building, police spokesman Evers said.
Weston served eight years in prison for killing her sister's boyfriend in the early 1980s, Ramsey said earlier. In that case, the victim "was held captive for an extended period of time, locked in a closet and he literally starved to death," he said.
"That concerns us because obviously, she's capable of quite a bit of a lot of different things," he said.
Asked why Weston is not still behind bars, Ramsey said Tuesday, "That's a good question. Our legal system is what it is, but you would think that someone who's committed a crime that horrific would still be in jail. But she wasn't, and obviously she wasn't fully rehabilitated, either."
Ramsey said he has a team of detectives working the case, and is likely to put a task force together for long-term investigation, because "this is not one that's going to end very quickly."
Weston is believed to have been in McLean, Texas, with some or all of the alleged captives. They then traveled to Florida and Philadelphia, Evers said. All seven had been traveling together, he said, but he did not know for how long.
A preliminary hearing for the first three suspects on the charges and evidence in the Philadelphia case was set for October 24. A formal arraignment will be held later.
CNN's Melanie Whitley, Tom Faust, Ross Levitt and Kyra Phillips contributed to this report.