(Adds security minister comments)
By Jorge Otaola and Richard Lough
BUENOS AIRES, Jan 9 (Reuters) - President Mauricio Macri was humiliated on Saturday after Argentina's federal police chief admitted a manhunt was still on for two of the South American country's most notorious criminals, hours after the government celebrated their capture.
A massive search involving helicopters, police commandos and sharpshooters for three prison fugitives convicted of drug gang-related killings appeared to have ended when Macri congratulated the security forces on his official Twitter account.
But as one of the three men, Martin Lanatta, was transferred under armed guard from a local police station in the farming province of Santa Fe to the capital Buenos Aires, confusion intensified over the whereabouts of the two others: Lanatta's brother Cristian and a third man, Victor Schillaci.
"We're still looking for the other fugitives," acknowledged Roman Di Santo, head of the Argentine Federal Police force.
The 13-day search operation for the men has gripped the Argentine nation and the revelation that two remain on the run will deliver an embarrassing blow to the new government.
In a tough worded statement, Macri's security minister, Patricia Bullrich, said the government had been mislead, perhaps with the intention of buying the escapees time as the dragnet closed.
"There will be a full investigation into this false information, which might have been meant to give the other two time to make good their escape," Bullrich said in a televised statement in Santa Fe.
Earlier, local police in the town of Cayasta, 570 km (354 miles) north of the capital nabbed Martin Lanatta after one stolen vehicle they were in flipped over and another got bogged down in a muddy track. Hours later a statement from the prosecutors' office said all three had been detained.
Their daring escape came two weeks after Macri took office. It raised concerns of outside help and a blame game erupted between Macri and officials in the government of former President Cristina Fernandez.
Security Minister Bullrich did not point the finger at any particular group. But her comments will deepen suspicions among Argentines that narco gangs and corrupt officials played a hand in the jail break and ensuing game of cat-and-mouse with hundreds of security agents hunting them down.
The trio were convicted over the 2008 killing of three businessmen in the pharmaceutical industry allegedly linked to an ephedrine trafficking gang in a high-profile case dubbed "The triple murder." Ephedrine is used for the production of methamphetamine.
The high-drama operation has focused attention on the growing muscle of drug gangs in Argentina and raised questions over their political connections.
"Drug trafficking has grown in the last decade like never before in our country because of the inaction or complicity of the last government," Macri said this week, vowing to take on the traffickers.
In August, two months before the presidential election, Martin Lanatta alleged Fernandez's cabinet chief, Anibal Fernandez, was involved in the ephedrine trade and had ordered the triple murder.
Anibal Fernandez has rigorously denied the accusation and prosecutors have not investigated the claim. (Editing by Meredith Mazzilli and Alistair Bell)
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