More than 20 Congolese soldiers have been detained in Tanzania for illegally entering the north-west of the country, Tanzania\'s army has said. They said they were pursuing rebels from the Democratic Republic of Congo seeking medical treatment in Tanzania, Lt Col Emmanuel Mcheri said. The heavily armed men were arrested after docking next to a police vessel at Kigoma port on Lake Tanganyika. DR Congo\'s mineral-rich eastern region is plagued by rebel groups. Lt Col Mcheri said the soldiers, who are still being questioned, were in possession of machine guns, grenades, pistols and many rounds of ammunition. \"They breached the security of our country by entering our country with heavy arms. I have already reported this to higher levels of government and am awaiting further orders,\" he told BBC Swahili. Local officials refused to comment on the matter. Despite a peace deal in DR Congo in 2002, ending a brutal five-year civil war, there is still violence in the the east of the country. UN peacekeeping troops have been backing efforts to defeat some militias operating in eastern DR Congo and to integrate other groups into the army. Some 42,000 Congolese refugees are currently in Tanzania, having fled fighting in eastern DR Congo, according to the UN refugee agency.