January 9th is Panama's Martyr Day

Martyrs' Day is a Panamanian holiday which commemorates the January 9, 1964 riots over sovereignty of the Panama Canal Zone. The riot started after a Panamanian flag was torn during conflict between Panamanian students and Canal Zone Police officers, over the right of the Panamanian flag to be flown alongside the U.S. flag.

U.S. Army units became involved in suppressing the violence after Canal Zone police were overwhelmed, and after three days of fighting, about 21 Panamanians and four U.S. soldiers were killed. The incident is considered to be a significant factor in the U.S. decision to transfer control of the Canal Zone to Panama through the 1977 Torrijos–Carter Treaties.