9th-grader allegedly shot, stabbed grandmother to death: Prosecutors The suspect, Logan Mott, 15, was taken into custody in Buffalo.

 -- A Florida woman allegedly killed by her teenage grandson was shot and stabbed, prosecutors said this morning.

Logan Mott, 15, a ninth-grader, is accused of killing his grandmother, Kristina French, 53, whose body was found in a shallow grave Friday in Florida, Erie County District Attorney John Flynn said.

Mott, who lives with his father in Florida, was staying with his grandmother while his father was on vacation, Flynn said at a news conference this morning. When his father came back on Wednesday, he found his home "in disarray" and guns missing from the home, Flynn said.

Mott was found this weekend in Buffalo, New York, where he was taken into custody after making a wrong turn on the Peace Bridge while allegedly trying to cross into Canada, Flynn said.

In the car were guns and a knife with what appears to be blood on it, Flynn said.

Mott was taken into custody on a grand theft auto warrant. On Tuesday, a judge in Florida issued an arrest warrant for murder.

Mott “adamantly denies responsibility for his grandmother's death," Dominic Saraceno, a lawyer hired by Mott's family, told ABC News today.

Saraceno asks "the public to not rush to judgment. We need to do a thorough investigation on both sides -- the prosecution and the defense."

"Today was the first time we heard any of the details about the actual crime," Saraceno said, adding that based on a "preliminary review from my perspective, a lot of the pieces just don't add up."

Saraceno told ABC News on Sunday, "My understanding is he has no history of crime, he's a ninth-grade student, he's a good student, he's well-liked by his classmates.”

Mott, who is being held without bail, is set to be arraigned on Friday in Buffalo, according to ABC affiliate WJXX in Jacksonville.