(CNN) -- Investigators have arrested a third suspect in the killing of a prominent doctor near Houston, Texas.
Dr. Jorge Mario Gonzalez was found dead at his ranch last month, police say.
The Texas Rangers arrested Misael Sotollo, 18, Tuesday evening in a Houston apartment, the Austin County Sheriff's Office said in a statement.
Sotollo and two others -- brothers Cristobal Galvan Cerna, 23, and Moises Galvan Cerna, 18 -- are charged with murder in the death of Dr. Jorge Mario Gonzalez. Bail has been denied for all three, according to authorities.
The doctor was chief of the critical care section at Houston's Methodist Hospital and "a pulmonary medicine leader," according to the hospital system's Web site.
Gonzalez was found dead August 22, after deputies responded to a 911 call of a burglary in progress at his weekend ranch, in a rural and isolated area outside Bellville, Texas, authorities said. Bellville is about 50 miles west of Houston.
The suspects were already at the home when the Gonzalez family arrived around noon, law enforcement officials said. The doctor was able to enter his home and obtain a handgun in an attempt to defend himself and his family, authorities said. Gunshots were exchanged, and the doctor died at the scene, they said.
Also wounded in the shooting was ranch hand Noel Galvan Cerna, who worked for Gonzalez and is the brother of two of the men in custody in the killing. Sotollo is their cousin.
An officer responding to the Gonzalez home on the robbery report was met by vehicles leaving the location, Austin County Sheriff's spokesman Sgt. Paul Faircloth said, and a person in one vehicle fired on the officer. Neither the officer nor his patrol car was struck, and the officer did not return fire, Faircloth said. The officer was able to provide a detailed description of the vehicles, he said.
The officer found Gonzalez' wife and toddler unharmed inside the home.