A St. Petersburg man accused of breaking a 6-month-old baby boy's ankles and skull last fall was arrested Thursday on a felony child abuse charge.

Abimael Alvarez-Estrada, 38, is being held in the Pinellas County jail on a $50,000 bond.

According to an affidavit, a doctor at All Children's Hospital noticed on Oct. 7, that the boy suffered from a left ankle fracture that was less than 24 hours old and a right ankle fracture that was between 4 and 7 days old. The doctor also noted that the child had a skull fracture that was several weeks old.

Alvarez-Estrada gave several versions of events while talking about the injuries with Pinellas sheriff's detectives, according to court documents. He told the detective that the baby's left foot had slipped under the mattress in a playpen and he pulled the child to dislodge it. He could not provide an explanation for the right ankle fracture. Alvarez-Estrada said he dropped the child in the bathtub and that's why the child has a skull fracture, according to deputies.

Dr. Sally Smith told deputies that Alvarez-Estrada's explanations are not consistent with the injuries, which are highly specific for physical abuse, according to the affidavit.

The defendant's mom, Margarita Estrada, said the baby boy is Alvarez-Estrada's son. She said the baby was not abused by Alvarez-Estrada.

“He’s a good person," Estrada said. "I don’t know why they took him away like that because if he would have hit the baby, he wouldn’t have taken the baby himself to the doctor.” 

Estrada said she believes the baby injured himself.

“The baby, like any baby, was probably playing around and he probably hurt his leg crawling," she said. “My son has never been in trouble and doesn’t have a record.”

The defendant's mother also questioned why it took so long to file charges.

"They took him after so much time," she said. "Why didn’t they take him the same day they took the baby?”

A Pinellas sheriff's office spokeswoman said the state attorney's office has been investigating the case since January and a judge signed a warrant for Alvarez-Estrada's arrest this week.

Estrada said the boy, who's now 1-year-old, is in DCF custody.