Unknown people toppled a statue of Spanish explorer Juan Ponce de León in the pre-dawn hours of Monday ahead of a visit of King Felipe VI to the U.S. Caribbean territory of Puerto Rico.

Col. José Juan García, police commissioner for San Juan, told The Associated Press that officers patrolling the cobblestone streets of the capital's historic district heard a loud bang at 4:30 a.m. and found the statue broken in pieces.

“It sounded like an explosion,” he said.

The statue was made of melted steel from British cannons and featured the Spanish explorer facing south with his left hand on his hip and right finger pointed toward the first settlement he founded. The ruins still mark the spot of the island’s first Spanish capital and is a U.S. National Historic Landmark. The statue also points in the direction of the nearby San Juan Bautista Cathedral that bears Ponce de León’s remains and is a popular tourist spot.

Two years ago, activists marched through the streets of Old San Juan as they joined a U.S. movement to eradicate symbols of oppression and demanded that Spain's legacy in Puerto Rico be erased. While some statues have been defaced with graffiti, police said this is the first time such a statue was toppled.

The statue was located in the Plaza San José, near the second oldest surviving Spanish church in the Americas, whose construction had begun by 1532 on land donated by Ponce de León and whose base was erected atop an Indigenous settlement.

The incident occurred just hours before King Felipe VI was scheduled to meet with Puerto Rico Gov. Pedro Pierluisi and other officials to celebrate the 500th anniversary of the founding of San Juan.

Christopher Columbus landed in Puerto Rico in 1493 accompanied by Ponce de León, who became the island's first governor and quelled an uprising by the native Tainos, a subgroup of the Arawak Indians. Puerto Rico remained a Spanish colony until 1898, when Spain transferred the island to the United States at the end of the Spanish-American war.