2 teen girls arrested for allegedly threatening mass casualty attack at Memorial High School

HARRIS COUNTY, Texas (KTRK) -- Two teenage girls are under arrest, accused of plotting a "mass casualty attack" on Memorial High School. The FBI says the plot involved pipe bombs and guns.

The girls accused of devising the chilling plot to harm students are 15 and 16 years old, according to the FBI. Their names were not released because they are juveniles.

Officials said they found out about the plan on Tuesday and deemed it concerning enough that they took the girls into custody that day.

The Spring Branch ISD police chief said the 16-year-old girl is a student at Memorial High School who has been attending an alternative school. She was arrested on a charge of making a terroristic threat.

The 15-year-old girl is a Willis High School student and is currently in custody on unrelated charges, according to the Montgomery County Sheriff's Office.

"This is a perfect example of state and federal law enforcement working together. This is exactly how this information, I think, should be handled and I'm grateful to the FBI that got us information right away and we were able to act on it very quickly," Chief Baimbridge with Spring Branch ISD police said.

Authorities said no guns, bombs, or bomb-making materials have been found in Harris County, though the investigation is ongoing both in Harris and Montgomery Counties.

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