Senator Ninoy Aquino revealed, what was known as Oplan Sagittarius on September 13, 1972, in a privilege speech, that President Ferdinand Marcos ordered a top-secret plan to place Metro Manila and nearby areas under the control of the Philippine Constabulary as a prelude to martial law.
Martial law was commenced on September 21, 1972, by virtue of Proclamation No.1081, proclaiming the state of Martial law in the Philippines.
Martial law was lifted on January 17, 1981.
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