GIBSONTON — A 26-year-old mother was arrested Wednesday on allegations that she set her ex-boyfriend’s home on fire, threatened to kill her 11-month old child and then ran away with the baby, according to the Hillsborough County Sheriff’s Office.Martha Morales-Santizo, of Wimauma, was arrested on charges of attempted murder, first-degree arson, violating a domestic violence injunction and making written threats to kill.The bizarre set of events started at about 4:20 a.m. Wednesday, deputies said, when Morales-Santizo set fire to a home on 12130 U.S. 41 S, said Cpl. Larry McKinnon. The fire cause $1,5000 worth of damage to the home and a vehicle.Inside the home was her ex-boyfriend, Jose Hernandez-Rojas, and the child they had together, 11-month-old infant Fabian Hernandez-Morales.Deputies said Morales-Santizo knew her ex-boyfriend was inside the home when she set it on fire, McKinnon said. Another person, Echaverria Lopez, 18, was also inside at the time.Morales-Santizo threatened to kill Hernandez-Rojas, their child and herself in a message she scrawled on the outside of the home, McKinnon said.She then took the infant and fled, deputies said, causing authorities to search for the child.Her ex-boyfriend told deputies that he saw her with a red gas can before the fire and recognized her handwriting. Morales-Santizo was arrested hours and the child found unharmed, deputies said.She was being held late Wednesday without bail.