The mother of a South Jersey man charged with killing his wife was herself charged Monday with helping her son conceal the crime, authorities said.

Jo Crosby, 67, of Sicklerville, was arrested at her home around 6:30 a.m. and charged with one count of hindering apprehension and one count of tampering with evidence by destroying records.

Son Kyle, 28, of Mount Laurel, was charged Jan. 13 with the murder of Erica Crippen, 26. Crippen's body has not been recovered.

"We believe Jo Crosby played a major role in helping her son Kyle conceal the crime of murder," Burlington County Prosecutor Robert Bernardi said in a statement. "She assisted his efforts to conceal the body of his wife, Erica Crippen, after he took her life."

Authorities have not said how they know that Crippen, a mother of two, is dead. They also have said little about the evidence against her husband, who is described by prosecutors as a drug addict who went on the lam while authorities searched for his wife.

In the statement, Bernardi declined to comment on the actions that led to charges against Jo Crosby, citing the ongoing investigation.

Jo Crosby was released on $12,500 bail and she was released after posting bond. A first appearance in Superior Court in Mount Holly was canceled, and efforts to reach her Monday were unsuccessful.

"If you love your mom, why would you put your mother in that situation? That's crazy," said Crippen's cousin Barbara Kellam of Lindenwold.

Kyle Crosby is being held in the Burlington County Jail on $1.2 million bail. He also is charged with two counts of endangering the welfare of a child.

Authorities began investigating Crippen's disappearance after her 7-year-old daughter from a previous relationship failed to return to school.

After Crippen disappeared, family members said, Crosby told relatives that his wife had left him, but had returned to their home intermittently.

The couple lived on the 5000 block of Aberdeen Drive with their 3-month-old daughter and Crippen's daughter. When authorities went to the home, Kyle Crosby said he had not seen his wife since they went together to a Cherry Hill pub on New Year's Eve.

The next day, Kyle Crosby fled, authorities said. He was apprehended in Bellmawr after running away from a traffic stop in Brooklawn.

Authorities have said investigators believe that several items found in the car's trunk "have evidential value." However, the arrest affidavit was sealed at the request of the Prosecutor's Office.

Crosby's criminal history includes arrests for drug possession and distribution, motor-vehicle theft, burglary, and aggravated assault, authorities said.

Family members believe Crippen is dead, Kellam said, because she would not willingly leave her daughters, who are in the care of relatives. They would like to have her remains recovered, she said.

Crippen would have celebrated her birthday March 8.

"Give us all peace. Let us get some closure," Kellam said. "It sickens us every day to live through this."

Anyone with information concerning Crippen's whereabouts is asked to contact Burlington County Communications at 609-265-7113.