Killed were Fernando Baylon, 30; Nestor Rido, a driver; and John Kenneth Taroy, 12, a pupil of the Mayamot Elementary School.
The truck driver, Rolando Sorilla, 41, surrendered to the police after the incident.
Reports said Sorilla was negotiating a downward portion of Marcos Highway in Barangay Mayamot at about 12:30 p.m. when he lost control of the wheel, sending the truck smashing into a passenger jeepney, Ridos owner-type jeep loaded with students, a motorcycle, two tricycles, and a parked water tank truck.
Those injured were identified as Ridos daughter, Marian, 8; housewife Elvie Baldo, 36, and her son Baldo, 8; Tresemay Crisostomo, 10; Earl Snider, 9; Maria Angelo Salmasan, 9; Miriam Bantique, 8; Donna Mae Bacaira, 11; Sarah Jane Garcia, 8; Abigail de Villa, 7; Jocelyn Alcase, 13, and Jerrylyn Dimate. They were rushed to the Amang Rodriguez Medical Center.
Sorilla said his truck, loaded with gravel and sand, had come from Cogeo, Marikina and was on its way to a construction site in Barangay Masinag.
Police are readying charges of reckless imprudence resulting in multiple homicide and physical injuries against Sorilla.