Toronto-based Braeval Mining Corp. said the three company employees and two consultants were working at its Snow Mine gold and silver project. It did not release their names.
The men were seized around 5 a.m. by about two dozen rebels of the leftist National Liberation Army, Colombia's second-largest insurgency, in a rural area of the Bolivar state municipality of Norosi, said the armed forces commander, Gen. Alejandro Navas.
The rebel movement, known by its Spanish-language initials ELN, is far smaller with an estimated 1,500 fighters than the Revolutionary Armed Forces of Colombia, or FARC, which is currently engaged in peace talks with the government in Cuba.
The ELN has been seeking peace talks, too, though without success. Unlike the FARC, it has not renounced ransom kidnappings.
Colombia's president, Juan Manuel Santos, is anxious to try to end a half century of civil conflict that economists say costs the country hundreds of millions of dollars a year in lost economic opportunity, especially in the mining sector. Miners in Colombia have traditionally paid tributes, or "war taxes," to rebels and other illegal armed groups in exchange for being allowed to exploit precious metals.
Braeval said in a news release that it was fully co-operating with Colombian authorities in seeking to obtain the men's safe release.
Chris Eby, a Braeval spokesman in Toronto, declined to give any details of the kidnapping or provide the identities of the people abducted. The company's stock price fell 20.45 per cent Friday.
The company, which went public in December, says on its website that it has options to acquire an interest in four adjacent mineral titles in the Snow Mine project, where it is looking for gold, silver and copper. It says it also holds or has applied for interests in Mexico, Peru, Honduras and Nicaragua.
A Canadian geologist who surveyed the 10-square-mile Snow Mine site last year, Darrel Smith, told The Associated Press that exploration was in its early stages. Company documents say Braeval planned to drill at least 10 holes during the first quarter of 2013 to obtain samples in an area where Smith said informal miners had dug shafts.
The area, in the San Lucas mountains, is a traditional ELN stronghold.
A regional security official, Jose Hilario Bossio, told the AP that the kidnapped men included engineers and geologists. He said soldiers and police were searching the sparsely populated area in the San Lucas mountains. The armed forces said it had put planes in the air to try to find them.
Canada's Ministry of Foreign Affairs said it was aware of the reported kidnapping of a Canadian in Colombia but provided no information on his identity.
The two Peruvians were identified as Javier Leandro Ochoa and Jose Antonio Mamani by Peru's consul in Colombia, Jorge Davila. It was not immediately clear if they were Braeval employees.
The chief of Colombia's anti-kidnapping police, Humberto Guatibonza, said he was aware of two other foreigners being held by kidnappers. He said one was from the Dominican Republic and the other from Guatemala and both were taken by common criminals rather than by illegal armed groups.
Colombia's vice-president, Angelino Garzon, appealed to the ELN to immediately free the five prospectors without condition.
Associated Press writers Frank Bajak in Lima, Peru, and Charmaine Noronha in Toronto contributed to this report.
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