According to General Jacquin, as he is today, a “killer” despatched from Tunis from the G.P.R.A. forced Si Mohamed — always the most reluctant of the Wilaya 4 leaders — to return to the fold, and imposed upon him the execution of his guilty peers. Lakhdar, Halim and Abdellatif were summarily put to death, while Si Salah — on account of his seniority and distinction as a maquisard — was ordered to make his way to Tunis and stand trial there. Many months elapsed, unaccountably, with Si Salah apparently still under arrest in Algeria. Jacquin’s B.E.L. attempted a cloak-and-dagger operation to liberate him, but without success. Then, in July the following year, Si Salah, evidently on his way to Tunisia at last, was killed in an ambush by a French patrol; little more than two weeks later, but in another corner of Algeria, Si Mohamed was also tracked down and killed in an opération ponctuelle mounted by the 11th Shock. The coincidence, and curious circumstances, of the deaths of the two leaders have encouraged anti-Gaullists in the French army to speculate, even today, that there may have been more to it all than met the eye. Undeniable it was that, following their deaths, no one was left on the Algerian side able to give evidence about the whole sad story of “Operation Tilsit”.

XREF: Connects to the broader account of Operation Tilsit and the French-Algerian covert contacts during the war's closing phase.

Horne, Alistair, A Savage War of Peace- Alge…, loc. 1192