Authorities dropped charges against the main suspect in the murder of a local man and former UCSB student at Hendry’s beach, arresting another man in his place.

Rudy Gallegos, 21, was released from custody last week after witnesses positively identified another man, 20-year-old Adrian Robles, as the alleged murderer of Robert Burke Simpson. Simpson, a UCSB alumnus and former Daily Nexus photographer, was stabbed to death on April 15.

According to the Santa Barbara County Sheriff’s Dept., witnesses said that Gallegos and Simpson had been involved in a confrontation prior to the stabbing, but it was Robles who actually stabbed the victim in the neck with a sharp object. Soon after, witnesses report, Gallegos entered a vehicle and started to drive away but was joined by Robles right before the vehicle departed.

According to Drew Sugars of the Sheriff’s Dept., deputies immediately began investigating both suspects’ involvement in the crime.

“Rudy [Gallegos] was under surveillance the entire time,” Sugars said. “We were able to track him through Sunday, and he was arrested a couple blocks from home in Santa Barbara.”

Authorities obtained a warrant and searched Gallegos’ home but found nothing that linked him to the murder. Gallegos was arrested April 18 on homicide charges, which have since been dropped.

“Meanwhile, deputies were looking for Adrian Robles, but at this point it wasn’t clear who was the one who stabbed Simpson,” Sugars said. “Until we did that, we needed to keep Rudy [Gallegos] in custody because it was not clear who the stabber was.”

A week later, deputies tracked down Robles at a home in Ventura County and arrested him for homicide. Deputies also searched Robles’ home in Santa Barbara, gathering enough evidence to take him into custody.

Authorities put the two men in a physical lineup and asked witnesses to identify Simpson’s stabber.

“There were multiple witnesses who pointed out that Robles was the one who actually stabbed Simpson,” Sugars said. “Based on evidence and witnesses, Gallegos was released.”

Throughout the investigation, deputies contacted approximately 60 to 70 people who were at the scene of the crime and interviewed over 40 witnesses.

In addition to Robles, authorities have identified two other suspects involved in the murder. Vehicle descriptions allowed officials to trace the vehicle seen leaving the scene of the crime to 19-year-old Brittany Weiler, who was arrested and charged with accessory to murder on April 16.

The following day, a 17-year-old minor was also arrested as an accessory to murder and transported to juvenile hall. Authorities allege the girl was present in the vehicle as Weiler drove both Gallegos and Robles away from Hendry’s beach.

While deputies do not know at this time whether the murder was affiliated with gang activity, they suspect it was gang-related.