"The mode of operation was very much like that of the (Alex Boncayao Brigade)," a senior investigator told The STAR.
"They even commandeered a public vehicle as getaway. If the killing was staged by hired goons, then everything should be taken care of including the vehicle they used in their escape."
Investigators said Rosimo was killed three days after the murder of Rodrigo Borgonio, chairman of Barangay Pansol in Quezon City.
The ABB killed the 48-year-old Borgonio, a known supporter of Quezon City Mayor Feliciano Belmonte Jr., investigators added.
However, Quezon City police director Chief Superintendent Napoleon Castro said his detectives are still trying to establish a link between the killings of Rosimo and Borgonio.
On orders of Philippine National Police chief Director General Hermogenes Ebdane Jr., the Criminal Investigation and Detection Group (CIDG) has spearheaded the investigation of the killing of Rosimo.
CIDG chief Director Eduardo Matillano said his men are coordinating with the Central Police District to determine the motive behind the Rosimo’s murder.
The shooting to death in broad daylight of Rosimo last Thursday shows that criminals are getting bolder and the police can no longer catch them, President Arroyo said yesterday.
"I am concerned about this trend of murders of public officials because they suggest a growing boldness of criminals and the failure of the law to get them," she said.
"I want the authorities to unearth the real motive behind the killing and to hunt down the perpetrators," the President added.
Mrs. Arroyo said she was concerned with the murder of Rosimo, who was a widower, a few meters from his home in Project 6, Quezon City.
"I sympathize with the bereaved family and I would like the law enforcement authorities to get to the bottom of the case," she said.
Meanwhile, Metro Manila police commander Deputy Director General Reynaldo Velasco said the killing of Rosimo was not part of a plot to embarrass the Arroyo administration.
"We have no report to that effect," Velasco said. "But I have ordered a thorough investigation of the incident until we have uncovered the motive behind the BIR executive’s ambush-slaying."
Sources at Camp Crame said the murder of Rosimo is "related" to the ambush of an official of the Bureau of Customs at Anda Circle in Port Area, Manila, and the killing of two Customs employees in Cebu City last July.
"We have seen a pattern here," a source said. "But we have no concrete evidence as yet to link Rosimo’s slaying to those of the Cebu and the Port Area incidents." — With reports from Marichu Villanueva, Non Alquitran