GREENWOOD, Ind. - Hundreds gathered Sunday night to mourn the loss of a Greenwood teacher and her husband who school employees said were killed in a blast that leveled two homes and damaged up to two dozen more on Indianapolis' south side.

Jennifer Longworth, a teacher at Southwest Elementary School, and her husband, John Dion Longworth, died Saturday night after an explosion at a home in the 8400 block of Fieldfare Way in the Richmond Hill subdivision, near Sherman Drive between County Line Road and Stop 11 Road, teachers and the school's secretary said.

Slideshow:  Explosion kills 2, levels homes

Eight others were injured in the blast and ensuing fire, which displaced at least 200 people.

A man identified by teachers as Jennifer Longworth's brother attended Sunday night's vigil, crying along with staff members, parents and students.

"It just made my heart sink," said parent Jennifer Taylor. "My son had her in second grade, and she did so much for him and she's done so much for all the kids here. It just saddened me so bad to hear the tragic news, that it was her."

"She was very nice," said student Courtney Conway. "She would always read us stories, and she would always hand out candy." 

Greenwood Schools Superintendent David Edds said the district's schools will open two hours late Monday so staff can prepare for how they will talk to students about what happened.

"How do you say something like that to the kids? How do you explain that?" asked parent Autumn Stivers. "I mean, they're 7 years old, and for them to lose someone so close to their heart, it's horrible. And it was in a horrible way. Just devastating for all of us."

Blake Pepper, Longworth's former student, said she would be remembered for her love of education.

"She was really nice and quiet. She liked us all," Pepper said.

John Dion Longworth was the director of product development and technology for Indy Audio Labs, an Indianapolis-based company in the consumer electronics industry.

"Throughout his more than 10-year career with our company, Dion's creative and technical contributions directly impacted the development of several award-winning consumer electronics products in public use," Rick Santiago, CEO and co-founder of Indy Audio Labs, said in a statement. "He will be missed by his co-workers at Indy Audio Labs and his industry colleagues and peers."

Authorities have not said what they believe caused the explosion. The Bureau of Alcohol, Tobacco, Firearms and Explosives and the National Transportation Safety Board, which oversees gas lines, were called in to help with the investigation.

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