MANILA, Philippines (4th update, 6:56 p.m.) — A magnitude 6.1 earthquake was felt in parts of Luzon Monday afternoon, the Philippine Institute of Volcanology and Seismology said.

According to PHIVOLCS, the quake hit Castillejos, Zambales at around 5:11 p.m. The quake was tectonic in origin. It earlier recorded a magnitude 5.7 quake before revising it to magnitude 6.1.

Reported intensities were Intensity 5 in San Felipe, Zambales and Quezon City. Phivolcs' scale describes Intensity 5 as a "strong shaking and rocking felt throughout the building."

Intensity 4 or "moderately strong" shaking which slightly rocked vehicles and was generally felt by those indoors and some people outdoors was recorded in Pasig City, Makati City, Caloocan City, Marikina City and Las Piñas City.

Areas of Meycauayan and San Jose del Monte in Bulacan as well as in Floridablanca, Pampanga; Villasis, Pangasinan; Tagaytay City; Villasis, Pangasinan; and Baguio City also experienced Intensity 4 tremors.

Earlier: 3-second video shows lights shaking during the earthquake here in BGC @PhilstarNews pic.twitter.com/9AQX1B2EwM — Rosette Adel (@rosette_adel) April 22, 2019

"Weak" Intensity 3 shaking felt by many indoors especially those on upper floors was experienced in Damariñas, Indang and General Trias in Cavite as well as in Lucban, Quezon; Muntinlupa City, Cabanatuan City; Palayan City; Gapan City; and Santo Domingo and Talavera in Nueva Ecija.

The STAR quoted presidential spokesperson Salvador Panelo as saying he was still checking on President Rodrigo Duterte's whereabouts during the earthquake, which prompted an evacuation of the Palace.

Earlier: Construction materials fall from building in BGC during the earthquake @PhilstarNews pic.twitter.com/U2cfx7nvoQ — Rosette Adel (@rosette_adel) April 22, 2019

In an interview on radio dzMM, Pampanga Gov. Lilia Pineda said there were reports of downed electrical posts after the earthquake. She said her office is also looking into reports of cracks on bridges and roads in the province, which is near the epicenter of the earthquake.

"Almost all concrete electric posts in the barangay in Lubao have fallen down," she said, adding an arch marking the boundary between Lubao and Bataan province had also collapsed in the earthquake.

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