Buenos Aires - At least 41 police officers died Monday and several more were injured when their bus drove off a bridge in northern Argentina, plunging into a dry riverbed, officials said.
Officials believe a tire blew out and caused the bus to veer off the bridge before dawn, falling some 15 meters (50 feet) with 60 border police aboard, said the emergency chief for the province of Salta, Francisco Marinaro.
Ten police officers were hospitalized, four of them in serious condition, he told a local radio station.
The bus was part of a caravan of three carrying police.
President Mauricio Macri sent his condolences to the officers' relatives.
"The Argentine people must stand with these families," he said.
A local mayor had originally said 20 people were killed in the accident, but the death toll rose as emergency workers recovered bodies from inside the mangled wreckage of the bus.
The mayor, Gustavo Solis of Rosario de la Frontera, said the road where the accident occurred is known to be in poor condition.
"Those of us who know the area try to avoid driving at night," he said.
The accident ocurred in a mountainous area with dense forests.
Security Minister Patricia Bullrich has traveled to the site of the accident.