Police identified the fatality as Lloyd Andrew Erfe, the driver of the pickup truck, of Barangay Cabaruan, Cauayan City, this province.
Cordon police, in an interview with a local radio station, said that the pickup truck was speeding on the curved road and collided with the oncoming truck with license plates CAE-7977 driven by Daniel Serrano, 59, of Bulihan, Rosario, Batangas at 3 p.m.
Police said Erfe might have fallen asleep behind the wheel.
The injured, Rocky Batongbakal of Jones, Christopher Cristobal of Reina Mercedes, and Brenzon Jann Salvador Perocho of Jones, all in Isabela, were taken to the hospital while the Diadi Police Station, Diadi Fire Station, and Cordon and Diadi rescue worked together to retrieve the body of Erfe trapped inside the pickup.
Efre was taken to the hospital but died on the way.
The victims had just delivered relief assistance to those affected by the flashflood and landslide in Banaue, Ifugao and were on their way home when the accident occurred.
The driver of the ten-wheel truck, who sustained minor injuries, is in police custody and Cordon police preparing the cases against Serrano.
Police are not discounting a settlement between the two parties.