The local government of Imus and member of the Philippine Navy conduct a rehearsal for the commemoration of the National Flag Day at the Heritage Park in Brgy. Alapan, Imus, Cavite on May 27, 2021. The event marks the 123-year-old Battle of Alapan on May 28 although presidential proclamation No. 374 officially recognizing the event was signed on March 6, 1965.