What is the test for an instruction of flight from the scene of a crime?

In general, a flight instruction is proper where the evidence shows that the defendant departed the crime scene under circumstances suggesting that his movement was motivated by a consciousness of guilt. [Citations.] [F]light requires neither the physical act of running nor the reaching of a far-away haven. [Citation.] Flight manifestly does require, however, a purpose to avoid being observed or arrested. [Citation.] Mere return to familiar environs from the scene of an alleged crime does not warrant an inference of consciousness of guilt [citations], but the circumstances of departure from the crime scene may sometimes do so. (People v. Bradford (1997) 14 Cal.4th 1005, 1055, 60 Cal.Rptr.2d 225, 929 P.2d 544.) Even though defendant returned to his apartment after the killings, where he was arrested the next morning, he was observed by a neighbor to start running from the scene of the crimes only when an alarm sounded. Contrary to defendant's argument, the circumstances of his departure from the scene provided sufficient evidence of flight to warrant the flight instruction.