The mother of two boys accused of helping to steal explosives from UA's San Xavier Mining Laboratory near Sahuarita was sentenced to two years' probation.

She had pleaded guilty to endangerment.

Authorities said she knew the boys, ages 12 and 16, had the explosives and told them to discard the items.

One of her sons has already been sentenced to probation and the other has a trial pending. Two other boys, ages 11 and 14, await sentencing.

Authorities say enough explosives were stolen from the lab to level a one-story building.

Initial reports stated that dynamite was stolen from the laboratory, but Hugh Miller, an associate professor and director of San Xavier Mining Laboratory, said that the explosives were not dynamite and were less dangerous than dynamite.

"They took Emulsion, which can't detonate without a blasting cap," Miller said, adding that Emulsion is harder to detonate than most other explosive because it requires a special blasting cap.

"If it was someone who knew what they were doing, they would have taken something else," he said.

The lab does not have any dynamite, Miller said, because it becomes unstable over time.

Miller said that since the theft the laboratory has left the case to the authorities.

"We're allowing the state and county authorities to make the best judgment for the university."