SKOWHEGAN – Two boys were charged with criminal use of explosives and released Sunday to their parents after setting off two homemade bombs inside a Wal-Mart filled with holiday shoppers.

The boys, both 15, were arrested late Saturday night.

Hundreds of customers were evacuated from the store when the bombs detonated Saturday afternoon, one in the toy section, the other in the pet food area.

At least eight people were treated by emergency medical technicians or at a nearby hospital for irritation to their eyes and throat or ringing in their ears, said Stephen McCausland, spokesman for the state Department of Public Safety.

The boys, whose names were not released because of their age, were taken into custody after photos from the store’s security cameras were shown on late night television newscasts.

The parents of one of the boys recognized him in the photos and met with investigators at the Skowhegan police station, McCausland said.

Investigators also said they had identified the two boys after showing the photos to teenagers at a local McDonald’s.

Both boys were charged with criminal use of explosives. They were released Sunday morning to the custody of their parents.

McCausland said he had no information on why the bombs were set off in the store and whether the two had been in trouble with the law before.

He said the boys had made three additional explosive devices and placed one on the roof of a downtown business and two on the lawn of a residence. Those three bombs, none of which had detonated, were retrieved by investigators, he said.

Investigators described the devices as acid bombs made from a concoction of common household products that cause a chemical reaction when mixed together.

Wal-Mart reopened as usual Sunday morning, and the manager of the store referred all questions about the incident to police.

McCausland said he did not know when the boys would appear in court.