Armed thieves have made away with about 33 kilogrammes of gold worth 1 million dollars after breaking into a gold mine safe deposit in northern Mexico, authorities said Thursday, according to dpa. A commando of four people with weapons assaulted the mine and retrieved the gold from a safe where it was being held ready to be exported to the United States, the authorities said Thursday. The robbery took place in the early hours of Wednesday in the town of Trincheras, in the Mexican state of Sonora, some 100 kilometres south of the border with the United States. "According to the complaint filed by the mining company Secotec, the commando threatened personnel and forced the manager to go to the safe where the gold was," Jose Larrinaga Talamantes, spokesman for the public prosecutor's office in Sonora, told Deutsche Presse- Agentur dpa. The company suffered a similar attack on April 6, when thieves took 16 kilogrammes of gold, the spokesman said. The gold stolen in the two episodes has a total market value of close to 1.5 million dollars. Larrinaga said attackers carried long weapons and wore military fatigues, according to the complaint.