To ascend to the position of “dragon head” of one of San Francisco Chinatown’s fraternal organizations turned criminal enterprises, Raymond “Shrimp Boy” Chow arranged the assassination of his predecessor, according to a federal grand jury indictment Friday.

The murder charge raises the stakes in an undercover five-year public corruption and organized crime probe that has already yielded racketeering charges against Chow and 28 others. The investigation also implicated a prominent former state Democratic senator, leading to his guilty plea.

Chow, 55, took control of Ghee Kung Tong in 2006 shortly after Allen Leung, its leader, was gunned down by a masked assassin at his import-export business. At the time of his death Leung, 56, was involved in Chinese community brotherhoods, or tongs, and had been appointed to city task forces by two San Francisco mayors.

In the wake of Leung death’s, Chow allegedly turned the fraternal organization Leung had led into a criminal group that was behind the trafficking of stolen goods, narcotics, bulletproof vests and guns, while also unleashing violence.

Prosecutors allege that Chow’s racketeering enterprise laundered $2.6 million in cash from illegal bookmaking.

The undercover FBI investigation led to a guilty plea from ex-state Sen. Leland Yee for taking bribes. Yee, the investigation revealed, was a close associate of Chow. Yee was accused of winning passage of a state Senate resolution honoring Chow’s organization in exchange for a bribe, as well as offering to broker a weapons sale.

Prosecutors also are alleging in the new indictment that Chow solicited the murder of Jim Tat Kong, a San Francisco gang member in 2013.

On Friday, Chow pleaded not guilty to murdering Leung, as well as charges including conspiracy to commit murder in “aid of racketeering.”

Two co-defendants in the racketeering case have pleaded guilty and implicated Chow in soliciting Leung and Kong’s killings, according to federal prosecutors.

Chow will now face two separate trials. His racketeering and money laundering case is slated to begin next month. A federal judge on Thursday decided that additional charges, including murder, would have to be tried separately from the racketeering charges.

Chow has contended in the past that he is a reformed figure who has bounced back from convictions for armed robbery, assault and pimping. His lawyers insist that he is being selectively prosecuted while other public figures whose conversations were captured in wiretaps were not indicted. In a recent motion his lawyers named San Francisco Mayor Ed Lee.

Two Human Rights Commission officials affiliated with Lee’s 2011 election campaign were caught in wiretapped conversations explaining how they planned to break up $10,000 donations — which exceed the limits under campaign finance law — into smaller amounts in the names of straw donors. One told an undercover agent that Lee was aware of the scheme. Lee has denied any wrongdoing.