(UPDATED) Mayor Rolando Espinosa Sr. of Albuera, Leyte shot at police before he was killed by authorities, an official said Saturday.

Espinosa and fellow slain inmate Raul Yap fired shots while being served a search warrant at the Baybay Provincial Jail in Leyte by operatives of the PNP's Criminal Investigation and Detection Group (CIDG) Region 8.

"Silang dalawa ang nagpaputok sa operatiba natin at napilitan po yung mga operatiba natin na gumanti at ito po yung nagresulta na ikinamatay ng mga suspek," said CIDG Region 8's Supt. Melvin Marcos.

[The two of them fired shots, prompting operatives to fire back, which resulted in their death.]

• READ: Albuera Mayor Espinosa shot dead inside jail cell

Marcos said they received information that Yap was dealing drugs inside the provincial jail, prompting them to seek a warrant from a judge.

The person sent to verify the claim confirmed the information and even found out that Espinosa was hiding a weapon inside his cell, he said.

With this, the judge issued warrants for both inmates Friday and the CIDG proceeded with the operation early Saturday.

Marcos, however, said they had encountered "resistance" from the jail upon arriving. When they were finally able to break through, he said Espinosa and Yap were ready to fire shots at them.

But no other inmate was hurt because operatives were able to tell them to duck, he said.

Marcos said they will be investigating the alleged non-cooperation of jail personnel and how the two inmates were able to sneak in drugs and weapons.

"Gaya po siguro ng mga droga, kung maipapasok ang mga droga sa loob po ng jail or Bilibid eh ganun din siguro ang proseso gaya ng pagpasok ng cellphone kung ganun lang po kadali yun hindi po imposible na yung baril maipasok din lalo din lagi dinedeklara ni mayor na under threat siya," he said.

[Maybe it's just like how drugs are usually brought into the New Bilibid Prison or maybe it's also how they sneak in cellphones, it shouldn't be impossible to do it with guns too, especially since the mayor has repeatedly said his life was in danger.]

'NARCO MAYOR'

Espinosa's death came just a week after Philippine police said it would be evaluating its strategy in the war against illegal drugs, hoping it would increase the number of arrests and lessen bloodshed.

Under the new plan, more resources would reportedly go into arresting prominent people tied to the illegal narcotics trade, including police, politicians and celebrities.

• READ: PNP ponders different tack in deadly drugs war

Espinosa was among the politicians linked by President Rodrigo Duterte to the illegal drug trade.

• READ: DUTERTE'S LIST: 'Narco' politicos, lawmen, judges

He was arrested in October for illegal drug possession. After several days, his son Kerwin, an alleged drug lord, was nabbed in Abu Dhabi.

The Albuera mayor was supposed to reveal the identities of around 30 individuals involved in the narcotics trade with his son, among them a senator, police and congressmen, but changed his mind for fear of his life.

But police said a list of officials and other personalities who received drug money from Kerwin included Senator Leila de Lima, when she was still justice secretary.

• READ: De Lima's name was on Espinosa's 'blue book,' cop says