Friday afternoon jurors in the murder trial of Border Patrol Agent Lonnie Swartz told Federal Judge Raner Collins they could not reach a verdict.
The jury has been deliberating for three days with a day off on Thursday.
Judge Collins told them to return to the jury room and keep trying, but late Friday afternoon, they went home for the day and will return on Monday.
Lonnie Swartz is charged with killing Jose Antonio Elena Rodriguez by shooting him through the border fence in October 2012.
Prosecutors have conceded the teen was assisting drug smugglers.
BP Agent murder trial for killing Mexican teen through border fence. Jury tells judge it can’t decide. Judge tells jury to keep trying. @kgun9
— Craig Smith (@csmithKGUNTV) April 20, 2018
Swartz testified he was protecting himself and other officers from rocks thrown over the border fence by people on the Mexican side trying to interfere with efforts to arrests smugglers who were trying to climb over the fence and into Mexico.
Swartz fired 16 rounds into Mexico through the border fence. Ten shots hit the 16-year-old Jose Antonio Elena Rodriguez.
Prosecutors say the threat against Swartz and other officers was not severe enough to justify deadly force and that they could have easily removed any threat by taking cover.