KISSIMMEE, Fla. -- A 19-year-old man was charged with first-degree murder after allegedly injuring his girlfriend's 2-year-old son and then pouring boiling water on the boy, who later died, Kissimmee police said.

Jonathan Alicea was initially arrested on a charge of attempted felony murder of Jariel Alexander, who was in critical condition at Arnold Palmer Hospital in Orlando. The charge was upgraded after the boy died on Monday, police said.

According to Kissimmee police, officers were called to the Osceola Regional Medical Center at about 7:15 p.m. Sunday in reference to a possible child abuse case.

Detectives talked with Alicea, who was the caretaker of the child when he was injured, and Alicea said he became angry with the boy because he would not eat and he soiled his pants, according to Kissimmee police.

Alicea told police he pushed Jariel's head, causing him to lose consciousness. He said he tried CPR, but when it didn't work, he poured boiling water on the child in an attempt to revive him.

"This is one of the worst cases that we've seen in quite some time," Stacie Miller of the Kissimmee Police Department said.

Alicea was arrested and transported to the Osceola County Jail, where he is being held without bond.

Alicea's brother, Chrstian Alicea, said he was surprised by the allegations.

"He loved the child like one of his own," Christian Alicea said

The Department of Children and Families has assumed custody of the mother's 6-year-old child.

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