It all started with police checking out what was called suspicious activity on the 800 block of Zavala Avenue.
"Nobody answered the door, and they started walking around the perimeter around the house," said Chief Ruben Villescas.
What they discovered in the backyard of this Las Milpas area home surprised them.
"They found 4 grenades," said Villescas.
Pharr police chief Villescas said it's an uncommon discovery, and police took the necessary precautions.
"They will cause destruction. They will cause death," said Villescas.
Which is why, Villescas said police didn't handle the grenades and neighbors were immediately notified.
Police said that neighbors weren't evacuated, but some neighbors did decide to leave as a precaution.
Eva Olivarez decided to stay home.
"It's very surprising when you hear of grenades," she said.
She said for the most part, this is a quiet neighborhood.
"I even sleep with my doors open and windows and everything," she said. "I don't lock up anything."
As for those who live at the residence where the grenades were found, Olivarez said, "They don't bother anybody. They keep to themselves."
But this neighborhood is just a couple of miles from the border, and Olivarez said it doesn't sit well with her that grenades were found in the neighborhood.
"I think I'll start locking up everything," said Olivarez.
The city of McAllen's bomb squad determined the grenades are not live.
Meanwhile, investigators are trying to track down the homeowners.
If you know anything about the grenades, call Pharr Crime Stoppers at 787-TIPS.