FORT WORTH -- A person of interest was taken into custody and a stolen vehicle found after an elderly couple was shot during a violent home invasion at their Fort Worth home.

The investigation and search for a suspect began after police were called to a home in the 10200 block of Cool Spring Drive at about 11:30 a.m. Tuesday. Authorities arrived to find John and Diane Porter, both 69, shot inside the home.

Although seriously injured, Mrs. Porter was able to call 911 and give authorities a description of the suspect. Homicide detectives joined the investigation due to the severity of the couple's injuries.

Authorities appealed to the public for help as they searched for a vehicle stolen from the home after they took a person of interest in custody. Police later reported the light blue, 2008 Kia Sorento was found in Terrell.

The Porters were transported to John Peter Smith Hospital. Police said John is in critical condition.

A separate car was located not far from the Porter residence. Police processed it before having a tow truck remove it.