You have a Fifth Amendment right against self-incrimination. If you are under investigation or have been arrested, make use of that right. Do not speak to detectives or cops. Do not discuss matters with friends or family members — even loyal loved ones may face subpoenas and be required to testify. Most of all, do not say anything about the matter on social media. Even people professing their innocence have been known to accidentally let details slip that later are used against them and cost them their freedom.
Instead, hire an attorney right away! Everything you say to your lawyer in an attorney-client relationship is privileged and confidential. Your lawyer can advise you about what to say and what not to say.