The attorney general's office on Tuesday obtained a court order forbidding Lenore Matusiewicz, 67, from having any contact with her grandchildren.
Jason Miller, a spokesman for the attorney general's office refused to say whether the girls were placed with another family member or were in state custody.
As investigators continued their probe into Monday's shooting and workers repaired shattered glass at the courthouse, David Matusiewicz made an initial appearance in federal court on Tuesday on charges that he violated his probation on the fraud and kidnapping convictions.
Wearing an orange jumpsuit with his hands cuffed behind his back, Matusiewicz was escorted into court. A federal magistrate ordered that he remain in custody pending a probable cause hearing Friday on the government's allegation.
Prosecutors say Matusiewicz sought permission on Jan. 8 to travel from Texas to Delaware, telling officials he would be staying with an uncle in Bayville, N.J., and that he failed to disclose that he spent Sunday night, the night before the shooting, at a home in Elkton, Md.
Telephone messages left at the New Jersey and Maryland addresses were not immediately returned.
Prosecutors also claim Matusiewicz is behind on child support payments of $2,200 a month and that he has yet to pay $9,674 in restitution and a $200 court assessment from his 2009 criminal case.
Lenore Matusiewicz attended Tuesday's hearing with another family member, but they declined to comment about Monday's shooting.
Ken Ryan from the Baltimore Field Division of the federal Bureau of Alcohol, Tobacco, Firearms and Explosives, said the weapon used in Monday's shooting, a Glock Model 21, was purchased lawfully last year from a gun dealer in New Jersey. Ryan said about three other weapons were recovered from Matusiewicz's vehicle.
Sherman contributed from Edcouch, Texas. Associated Press writer Brett Zongker in Washington also contributed to this report.
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