Washington/Mexico City - The United States Friday said the slaying of Mexico's top police and drug-fighting official brought home the urgency of shutting down the drug trade that plagues the US and its neighbour to the south.

Gordon Johndroe, spokesman for the White House's National Security Council, was referring to the murder Thursday of Edgar Eusebio Millan Gomez, who has variously been identified as the acting chief and the national police chief of Mexico.

The death of Gomez, 41, at the hands of "one of Mexico's drug cartels" was a "tragic loss for the people of Mexico," Johndroe said.

"This calculated attack against one of Mexico's top law enforcement officials demonstrates the urgency for the United States to assist our neighbor to the south, as well as protect Americans here at home," Johndroe said.

Gomez was identified by US media as the highest ranking victim of an all-out attack by Mexico's drug cartels since President Felipe Calderon declared war on the drug trade 17 months ago.

The New York Times reported that he was ambushed and hit by eight gun shots in the chest by several men wearing rubber gloves. He was entering his apartment building in Mexico City with two bodyguards when he was shot.

Even as Calderon on Friday was honouring Gomez for paying the ultimate sacrifice, another top police boss - Esteban Robles Espinosa - was mowed down by gunfire to the chest and head. Robles Espinosa had commanded the anti-kidnapping group of the judicial police in the Mexican capital.

Another two top Mexican police officials have also been killed since last Saturday.

Johndroe, who was speaking from President George W Bush's Texas ranch in Crawford, said Bush urges the US Congress to fully fund the Merida initiative - the president's 1.4-billion-dollar multi-year proposal to help Mexico and Central American nations "help secure their citizens and ours."

David Johnson, assistant US secretary of state for international narcotics, recently estimated that 90 per cent of the cocaine consumed in the United States transits or is produced in Mexico. Most of the methamphetamine consumed in the US is also produced south of the border.

In the first three months of this year, more than 700 people were killed by organized crime in Mexico, media reports said.

Earlier this month, several placards appeared in the northern Mexican state of Sinaloa with threats to anti-drug security officers signed by drug boss Arturo Beltran.

"I am going all-out. Let you know that, policemen-soldiers. So that it's clear. 'El Mochomo' is still there. Sincerely, Arturo Beltran," one of the placards read.

According to Mexican media reports, the death of Millan-Gomez occurred as he returned from an action against members of Beltran's gang, where nine people close to the drug boss were arrested. (dpa)