SANAA - Yemen said on Sunday it arrested two Europeans for weapons training in the center of the country, while Shi'ite rebels shot dead an accused government collaborator in their war with Sanaa. The Interior Ministry said in a statement that one of the Europeans had an Arabic name and the other was a non-Arab. The two were 24 years old but the ministry did not specify which country they were from. "Security forces in Dhamar province arrested two foreigners carrying the nationality of one of the European countries for practicing weapons firing," the statement said. Yemen, struggling to stabilize a fractious country strategically located next door to Saudi Arabia, jumped to the forefront of Western security concerns after al-Qaeda's Yemen-based regional arm claimed responsibility for an attempted December attack on a US-bound plane. Western countries and Saudi Arabia fear al-Qaeda is exploiting the instability in Yemen to recruit and train militants for attacks in the region and beyond. The killing of the government collaborator was one of the first signs of violence since a February truce deal between the government and northern rebels whose fight drew in neighboring oil exporter Saudi Arabia last year. The Interior Ministry said that some of the rebels, who have fought the government on and off since 2004, had opened fire on two men in the Saada region, where most of the fighting took place. One died while the other was in critical condition. "Houthi rebels targeted the two young men as revenge for cooperating with the government during the war on Houthi rebel strife in the Saada province," the Interior Ministry said.