Superintendent Conrado Laza, city police chief, admitted that investigators are still facing a blank wall on the killing.
"So far, we cannot point to anyone as the suspects behind the killing. The investigation is still going on. (There are) no suspects yet," Laza said.
The regional office of the Criminal Investigation and Detection Group (CIDG) is spearheading the probe upon the request of Chief Superintendent Isidro Lapeña, Southern Mindanao police director.
"There are so many angles that we are now exploring but we still could not say who was definitely behind it," Laza said.
According to the police crime laboratory here, the 22 spent shells found at the crime scene came from various types of guns, including an M-16 rifle, an HK Israeli-made rifle or Ultimax and an Armalite Colt.
Pala sustained nine gunshot wounds in the left arm, chest and heart in what was the third attack on him since last year.
Due to death threats, Pala had been broadcasting his daily radio program from his residence in recent months.
Pala’s wife, Louie, 38, said she does not expect any justice for her slain husband.
"I have learned to leave it to God because I know we will never have any justice here," she said.
A long queue of mourners has been flocking to Pala’s wake at Angel Funeral Homes here.