A fourth suspect, identified by Pasadena police as Idalene Yvannia Alvarado, 19, of Rowland Heights, is at large.
The latest arrest was made Tuesday night when the suspect, 19-year-old Gabriel Anthony Mixco of Rowland Heights, walked into the Pasadena Police Department and surrendered to detectives.
Two other suspects, 19-year-olds Juan Medina of Rowland Heights and Dominic Guzman of Hacienda Heights, surrendered to police on Monday. All three teens were booked for attempted murder and robbery. They are being held on $1,055,000 bail each.
Police say the four suspects attacked the elderly Pasadena resident while he was on a morning walk on West Drive, north of Salvia Canyon Road. The suspects took the man's ID and credit cards.
The victim suffered major head trauma and remains in critical condition.
If you have any information about this incident, you're urged to contact the Pasadena police dispatch at (626) 744-4241.