Roughly eight hours after they were found, the bodies of three people that were shot to death were removed from a home on the 9600 block of Vale Drive.
Officers came to the house to conduct a welfare check after someone from Minnesota called San Antonio police concerned about one or both of the males who had not reported for their duties as truck drivers since March 6.
The first officer to arrive at the home around 9 a.m. Thursday found that it was locked but could hear the television.
After noticing a broken window covered in tape, the officer cut through the tape and pulled back a curtain to find an elderly man sitting in a chair in a living room with a gunshot wound to the face.
Police found a younger man dead in a bedroom and an elderly female dead in a bed in a second bedroom.
All three had been shot.
"It appears that the elderly gentleman is the one that pulled the trigger," said San Antonio police Chief William McManus.
Police removed dozens of large firearms from the house during the investigation.
A rifle was used in the crime, according to SAPD.
Crime scene investigators had to wear masks while inside the home.
"Its not a fresh scene. They've been there for a while," McManus said.
"I'm still in shock," said neighbor Cristina Carion, who would see the elderly female victim at neighborhood garage sales or while getting the mail.
McManus reassured neighbors that the crime was an isolated incident.
"I was walking around letting people know what it appeared to be and there wasn't any reason to be afraid, that there wasn't any danger in the neighborhood from this," he said.
The elderly couple was renting the house, and the man who owns it said that all three victims were a family.
Police say there was no sign of forced entry into the home. The identities of the victims had not been released as of Thursday evening.
No word yet on a possible motive.