Senior Superintendent Federico Terte, Laguna police director, identified the fatalities as Jimson Vergara, 17; Arnold Munecia, 33; John Andrew Belen, 22; and Blas Melvin Dequina, 15.
In critical condition at the San Pablo Medical Hospital were Joey Belen, 21, and Aldwin Villaruel, 20.
Investigators said five men on board an unlicensed white Toyota Corolla opened fire at the victims at about 12:30 a.m. in front of the houses of one of them at Miraflor Subdivision in Barangay Del Remedio.
Joey Belen told police that their attackers were at least 20 years old, of medium build and wearing baseball caps.
Chief Superintendent Jesus Versoza, Calabarzon (Cavite, Laguna, Batangas, Rizal and Quezon) police director, said the shooting could have stemmed from a feud between youth gangs.
Investigators said the victims could have had a spat with their attackers when they attended a coconut festival in the city proper.
Police, however, were still probing other angles. Superintendent Elmo Sarona, San Pablo City police chief, heads a special task force that would go after the gunmen.
With Sarona in the task force are Chief Inspector Joseph Nartatez, intelligence and investigation chief of the Laguna police, and Superintendent Henry Daaca, provincial chief of the Criminal Investigation and Detection Group.
Police found six slugs and eight spent shells from a caliber .45 pistol and 15 spent shells from a 9-mm revolver at the crime scene. — With Ed Amoroso