The start of the four-day-long Libyan–Egyptian War.

The Egyptian–Libyan War, also known as the Four Day War, was a short border war fought between Libya and Egypt that lasted from 21 to 24 July 1977. The conflict stemmed from a deterioration in relations that had occurred between the two states after Egyptian President Anwar Sadat had rebuffed Libyan leader Muammar Gaddafi's entreaties to unify their countries and had pursued a peace settlement with Israel in the aftermath of the Yom Kippur War in 1973. Soon thereafter Libya began sponsoring dissidents and assassination plots to undermine Sadat, and Egypt responded in kind to weaken Gaddafi. In early 1976 Gaddafi dispatched troops to the Egyptian frontier where they began clashing with border guards. Sadat responded by moving many troops to the area, while the Egyptian General Staff drew up plans for an invasion to depose Gaddafi.