A Pennsylvania man died a hero early Sunday morning when he was shot in the head while defending his sister from her ex-boyfriend.

Police are searching for 31-year-old Yeicop Menjivar, who will face murder charges for shooting 24-year-old Kenito Montoya, WPVI reported.

Police said Menjivar came to the family home in Upper Darby Township early Sunday morning demanding to speak with Montoya’s sister, his former girlfriend.

“She woke up. Her and Yeicop went down to the first floor and they were engaged in a verbal, heated argument. At some point, the girlfriend’s brother intervened,” Upper Darby Police Superintendent Tim Bernhardt told KYW.

“That proceeded down to the basement, where they got into a physical altercation. and Menjivar pulled out a handgun and shot the brother in the forehead,” said Bernhardt, according to WPVI.

Montoya’s father told the station that Menjivar, who he called “the assassin,” “came to the house to kill her because she didn’t want to be with him.”

Nahun Montoya told KYW that his son “was a great person.”

“He saved her,” he said. “He died a hero.”

Bernhardt agreed.

“The brother did what any brother would do,” he said. “He intervened and tried to prevent his sister from being harmed. Unfortunately, Yeicop Menjivar turned his anger and you know, ultimately took his life.”

Police said Menjivar is believed to be driving a blue Honda Civic with Pennsylvania tags LWH4182 and is considered armed and dangerous.

Montoya’s family urged Menjivar to surrender.

“If there’s a family member of his familiy hiding him, please turn him in to the police,” they said.

For the latest true crime and justice news, subscribe to the ‘Crime Stories with Nancy Grace’ podcast.

[Featured image: Yeicop Menjivar and his car/Upper Darby Township Police Department]