CNN has reached out to Austin police and fire for more information.
Around 2:30 p.m., the police said the suspect was still at large and asked residents to shelter in place.
During a press conference, Austin Police Department Chief Joseph Chacon named Stephen Broderick, 41, as a tentative suspect and said officials made a decision to release Broderick's name because he was not in custody and was considered armed and unsafe.
"We don't know if he is in a vehicle or on foot", Chacon said.
They are now looking for the shooter, according to KXAN.
Austin-Travis County EMS said three adults were pronounced dead on scene.
When officials arrived on scene, two women and a man were found shot to death outside an apartment building. No other injuries have been reported at this time.
Austin police, SWAT and medical personnel respond to an active shooter situation located Great Hills Trail in Northwest Austin, Texas, on Sunday, April 18, 2021.
This is a developing story and will be updated.