Bow-ties are Nation of Islam members (often 'security' or, in other words, enforcers). Bow-ties are rumoured to be assassins, those killed are believed to have upset the Nation of Islam for mysterious offences. They may or may not be affiliated with one mob or crew, and might take sides in drug wars, or remain neutral, depending on their preferences.
"Notorious B.I.G. did something to piss off the Bow-ties."