Is a warrantless arrest valid if it is supported by probable cause?

"A warrantless arrest is valid if it is supported by probable cause." United States v. Hoyos, 892 F.2d 1387, 1392 (9th Cir.1989), cert. denied, 498 U.S. 825 (1990). Probable cause exists when reasonably trustworthy facts and circumstances within an arresting officer's knowledge would lead a prudent person to believe that a suspect has committed, is committing, or is about to commit a crime. Id. Further, the arresting officer need not have personal knowledge of the facts sufficient to constitute probable cause. "Probable cause may be based on the collective knowledge of all of the officers involved in the investigation and all of the reasonable inferences that may be drawn therefrom." Id.