The father of a 3-month-old boy who was found murdered near the Galveston seawall turned himself into police in Pennsylvania, saying he intentionally murdered the boy by repeatedly stomping on him, MyFOXHouston reports.

Travis Mullis told Pennsylvania investigators he repeatedly stomped on the 3-month-old until he felt his skull collapse, according to an official Galveston Police Department document. Mullis turned himself in Friday afternoon, where his bond was set at $1 million, police said at a Friday night news conference.

The baby boy was discovered by a bird-watching couple on Tuesday morning in an area known as Cherry Hill. The boy was found with a car seat near by, wearing nothing but a clean diaper.