A juvenile was also charged in connection with the incident.
Witnesses, including Dorado and two detectives, testified on Monday as to what allegedly led to and followed the incident.
Santa Monica Police Det. Daniel Larios testified that Castillo told police he approached Ovoian's group because he was annoyed when Ovoian was claiming to be part of a Hispanic gang, since Castillo used to have friends in the gang growing up.
Attorneys for the defendants argued that Castillo instigated a fight armed with a knife, and that Ovoian was defending himself while the other two defendants were attempting to break up the fight or standing nearby.
But prosecutor Heather Steggell argued Ovoian stabbed Castillo 11 to 13 times while Bagdasaryan and Akbari "aided and abetted" by restraining and beating him. Steggell claimed that there was "zero evidence" Castillo had a knife when he approached the suspects.
Dorado, the second alleged stabbing victim who had been drinking beer and fishing on the pier with Castillo, testified Monday that Ovoian approached him unprovoked and stabbed him four times.
After the fight, a witness told police that he saw Ovoian throw a knife into a trash can, and surveillance video shows him throwing another object into the ocean, where a dive team recovered another knife, police testified.
DNA tests are pending on five knives that may have been involved in the incident.
After the incident, detectives discovered a blood stain on both Bagdasaryan's shoe and Akbari's jacket, as well as "quite a bit of blood" on Ovoian's clothing, Larios testified.
Bagdasaryan and Akbari's attorneys argued that if they were involved, there would be more than just one blood stain on their belongings.
Follow Alene Tchekmedyian on Google+ and on Twitter: @atchek.
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