San Francisco Chronicle cites Peter Lance’s reporting: July 1st, 2013:
Discussed in Wikipedia entry on alternative theories of the crash.
In his book Cover Up: What the Government Is Still Hiding About the War on Terror,  Peter Lance wrote that TWA 800 was blown up by a bomb intended to disrupt the trial of terrorist Ramzi Yousef, the nephew of Khalid Shaikh Mohammed and planner of the 1993 World Trade Center bombing. Using official FBI 302s (informant documents), Lance asserts that Ramzi Yousef orchestrated the attack from prison in an effort to get a mistrial for master-minding the Bojinka plot. Lance claimed that the FBI had prior knowledge of this plot from a prison informant, but did not act on it. Lance cites similarities to Operation Bojinka, a prior plot developed by Yousef and Mohammed in which a very small (and thus more easily carried on board) “blasting cap” device could theoretically be used to ignite the plane’s fuel tank. Backing the theory is the fact that the FBI found residues of RDX, the same explosive that would have been used in a bomb like this. The occurrence of a similar incident (i.e. the explosion of TWA 800) while Yousef was safely in custody could have been used to justify a mistrial.
However, it was later assumed that the RDX residue came from a K-9 unit training exercise for a bomb sniffing dog in which RDX was placed within the plane for the dog to sniff out. This exercise occurred at St. Louis airport about 1 month before the explosion of TWA 800′s center wing fuel tank. The tail number of the plane which the training exercise took place was apparently not recorded, it was only noted that it took place on a “wide-body” aircraft, where three planes matching that description passed through the airport that day. Lance actually interviewed Herman Burnett, the K-9 officer who conducted the test and he told Lance that he believed that he’d done the test on another 747 — not the plane that became the fatal flight. This revelation shattered the FBI’s only explanation for the presence of high explosive residue on the passenger deck above where the fuel tank exploded. Lance suggests the decision to ignore that evidence was due to a Yousef-type RDX Bojinka-style bomb, possibly placed by Khalid Shaikh Mohammed or his operatives. Lance further interviewed William Tobin, the FBI’s chief metallurgist who claimed that there was “no indicia” of bomb damage on TWA Flight 800. But when Lance asked him what he had used as a model to reach that conclusion: the bomb aboard Pan Am Flight 103 or the casio-nitro IED Yousef placed aboard Philippines Airlines
Flight 434 in a test of the Bojinka device on December, 11th, 1994  Tobin admitted that he didn’t even know of the PAL 434 bombing incident. Lance contends that the decision by FBI and Justice Department officials to blame the crash of TWA Flight 800 on a fuel tank accident vs. an act of terror, was to impeach the credibility of Gregory Scarpa Jr. a capo in the Colombo crime family who spent 11 months from 1996-1997 in an FBI directed sting of Yousef while he was housed at the Metropolitan Correctional Center (Federal jail in Lower Manhattan). Scarpa Jr., whose father Gregory Sr. had been a Top Echelon Criminal Informant (TECI) for the FBI for more than 30 years, was going to argue at trial that the crimes he had been indicted for were at the direction of his father while he was a TECI and thus sanctioned by the Justice Department. Thus, Lance contends, in order to undermine Scarpa Jr.’s credibility and preserve a series of 75 Mafia prosecutions in the Eastern District of New York (EDNY) a decision was made by various DOJ officials to discredit Scarpa Jr. and thus ignore Yousef’s connection to the crash of TWA 800. One of the most significant revelations by Yousef documented in a series of FBI 302 memos obtained by Lance  was a threat Yousef had made to put a bomb on a U.S. airliner during his Bojinka trial so that he would get a mistrial. The crash of TWA Flight 800 occurred on the eve of the most damning evidence against Yousef being admitted at trial and the very day after the crash Yousef, who was representing himself in federal court asked the Judge for a mistrial..
Al QAEDA MEETS THE MOB:
302s memorializing a sting by Mafia capo Greg Scarpa Jr. of al Qaeda terrorist Ramzi Yousef at the MCC — federal jail in Lower Manhattan from March 1996 to February 1997. The one below from March 5th, 1996 describes how Yousef told Scarpa Jr. that during the upcoming Bojinka trial in which he was being prosecuted for a plot to put 12 bombs aboard U.S. bound flights exiting Asia, his cohorts on the outside would “blow up a plane”…. “so a mistrial would be declared.” The very next day after the crash of TWA Flight 800, Yousef, who was representing himself at trial in the Southern District of New York, asked for a mistrial.
In his second HarperCollins book “Cover Up,” Lance shatters the FBI’s only theory for the presence of high explosives found on the wreckage ABSENT a bomb. He also reveals that the FBI’s chief metallurgist concluded that there was no “indicia” of bomb damage on the fatal flight WITHOUT considering the “wet test” of an Improvised Explosive Device (IED) that Yousef performed aboard Philippine Airlines Flight 434 on December 11th, 1994.
Below see Appendix from Peter Lance’s 2004 book COVER UP showing the TWA gate assignments from June 10th, 1996 at Lambert International Airport in St. Louis