A 5-year-old boy is in critical condition with severe burns after he allegedly started a fire in his grandmother's Brooklyn apartment to punish her.

Jay Morales was angry about being reprimanded and planned to burn his grandmother's apartment down in revenge, police told the New York Post and MyFOX New York.

The blaze at Nancy Herrera's apartment in the three-story building on Knickerbocker Avenue broke out about 3 p.m. Monday, the Fire Department of New York said.

Police said the boy called 911 on Sunday night claiming his grandmother had died, according to the Post. But firefighters arrived to find her unharmed. Herrera tried to save her grandson, but he was engulfed in flames, so she escaped.

The next day, Jay allegedly told friends he planned to burn the house down after Herrera wouldn't let him go out and play.

The blaze appears to have started when the curtains were set on fire with a cigarette lighter, the Post reported, but the FDNY said the cause is under investigation.

Jay is being treated at New York-Presbyterian Hospital, according to MyFOXNY.com.

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Click here for the full story at the New York Post.

The Associated Press contributed to this report.