A Southwest Philly man is on the run after killing his ex-girlfriend’s brother in Upper Darby, police say

Keneri Montoya Santos died trying to protect his sister from an abusive ex-boyfriend who had broken into her Upper Darby home.

The man police believed killed him, Yeicop Menjivar, is still on the run more than a week after the fatal Feb. 4 shooting.

Menjivar, 31, is facing first- and third-degree murder charges, as well as burglary and gun offenses, according to the affidavit of probable cause for his arrest. He was last seen fleeing his ex-girlfriend’s home on Kent Road in a blue Honda Civic with the license plate number LWH-4182.

Upper Darby Police Superintendent Tim Bernhardt said Monday that Menijvar, who also goes by Yieco Menjivar Pacheco, is considered armed and dangerous and urged anyone who sees him, or anyone who may have assisted him, to call police.

“He knows he’s being wanted,” Bernhardt said, “so he’s going to flee and do whatever he can to protect himself.”

Santos, 24, was shot in the head and remained on life support for a few days until his organs could be harvested for donation, according to his family.

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In a statement, they called the native Honduran a hero who saved his older sister from “an assassin,” something Bernhardt said he agreed with.

“What saved her without a doubt was her brother intervening, and he directed his anger at her brother,” he said. “I do believe [Santos] saved her from further harm.”

Upper Darby police were called to Santos’ sister’s home on Kent Road around 2 a.m. on Feb. 4 for reports of a shooting, the affidavit said. They found him there, shot once in the head, and transported him to Pennsylvania Presbyterian Medical Center.

Another of his sisters told detectives that Menjivar had broken into the apartment earlier that evening and knocked on the door of the bedroom where she, her sister, and her children had been sleeping, according to the affidavit. Menjivar, dressed in black and wearing gloves, demanded to speak with her sister, whom he had previously dated.

The two had broken up on Dec. 30 after getting into an argument in the home, one serious enough that police were called, the affidavit said.

As the former couple went downstairs to talk about that earlier dispute, Santos arrived home and demanded that Menjivar leave. The two men then went behind the house to talk, and got into an argument that escalated into a fistfight, according to the affidavit.

During the fight, Santos’ sister told police she saw Menjivar pull out a handgun and shoot Santos in the forehead.

Menjivar then ran back through the home, stopping to tell his ex-girlfriend, “I warned your brother,” according to the affidavit.

Traffic cameras recorded the Honda Civic that Menjivar used to flee the home driving around Upper Darby. Police later learned that the man the car was registered to had put it in his name as a favor to Menjivar, a friend of his, the affidavit said.

Anyone with information about Menjivar is asked to contact Upper Darby Police at 610-734-3439 or 911.