Illinois police arrest girlfriend of Romeo Nance, the suspect accused of killing 7 family members

 Kylie Cleveland-Singleton has been charged with obstruction of justice

Police in Illinois have arrested the girlfriend of Romeo Nance, the shooter accused of killing seven family members in serial killings at two homes last weekend before taking his own life earlier this week in Texas.

The Joliet Police Department says 21-year-old Kylie Cleveland-Singleton is now being held in the Will County Adult Detention Facility on charges of obstruction of justice.

"Upon locating Cleveland-Singleton, she voluntarily agreed to be transported to the Joliet Police Department for questioning in reference to the murders," police said in a Facebook post. "After questioning Cleveland-Singleton, detectives believed he made statements designed to prevent the arrest of the suspect and hinder this investigation."

Nance was eventually found by U.S. Marshals near Natalia, Texas at about 8:30 p.m. According to police, he shot himself with a handgun and committed suicide after a confrontation with law enforcement there on Monday.

Investigators say seven members of Nance's family were killed Sunday at two homes on West Acres Road in the Chicago suburb.

They were identified as Nance's mother Tameka Nance, 47, her aunt Christine Astor, 38, her uncle William Astor II, 35, her brother Joshua Nance, 31, sister Alexandria Nance, 20, and 16 and 14-year-old sisters.

“During this investigation, detectives immediately identified 23-year-old Romeo Nance as a suspect in the murders that occurred on West Acres Road and it was believed he was involved in a fatal shooting along with the Will County Sheriff's Office. Non-fatal shooting in Joliet,” the Joliet Police Department also said.

Authorities say Cleveland-Singleton was the mother of Nance's 3-year-old son.

The motive of the firing is not clear.

"We can't get inside his mind," Joliet Police Chief Bill Evans told reporters Tuesday, according to the Associated Press. "We have no clue why he did what he did."

Police say, "This investigation is active and ongoing as evidence technicians continue to process the large amount of evidence."