A 3-year-old boy was taken to the West Penn Hospital burn unit on Christmas day, suffering from second-degree burns on his legs and genitals from apparently sitting in dirty diapers for days.

The boy's father, Jesus Rodriquez, 34, of Greensburg, has been arrested and charged with aggravated assault after police discovered the 3-year-old and his 4-year-old sister in an apartment filled with soiled diapers; smeared feces and garbage.

According to an affidavit of probable cause, the children's uncle, who lives in the same building, went to see them on Christmas, but when he entered the apartment and tried to pick the boy up, "the child instantly began screaming in pain."

The uncle called 911, and when police arrived, "the child was observed standing, bent over the living room couch, shaking and upset, obviously in pain and severe discomfort."

Police described his legs as being "bright red, consistent with the loss of several layers of skin," extending from the waistband down to the backs of his knees. He was wearing only a shirt.

The uncle told police that the boy routinely would go extended periods of time wearing the same diaper.

The 4-year-old girl also had what appeared to be a burn injury to her leg, which police said looked less than a week old and had not been treated.

She was taken to Westmoreland Hospital. A doctor there said the girl appeared to have an old, dirty skin wound. Further, she had redness to her scalp and genital area from lack of grooming.

When police attempted to talk to Mr. Rodriguez, they said he appeared to be under the influence of an unknown substance. Officers found two empty cough syrup bottles on the back of the couch behind the man's head.

Mr. Rodriguez blamed the condition of his apartment on his son's "misbehavior, indicating that he was jumping too much," the affidavit said.

Police said the man was evasive in answering questions, but they weren't sure if that was intentional.

"When asked when he had last changed the child's diaper, he stated that it was [Thursday.] When asked what time, he stated, 'not too long ago.'

"At times, he would laugh and the situation and would continue to be incomprehensible, mumbling and not making sense when speaking," the report said.

Mr. Rodriguez was arrested on an outstanding bench warrant for drug charges in Philadelphia.

In addition to the aggravated assault count, he is also charged with endangering the welfare of children; reckless endangerment and simple assault.

A preliminary hearing for Mr. Rodriguez is scheduled for Jan. 8 before District Judge James Albert.