( CNN ) -- A fight for the control of Sake , a strategically placed town in the eastern part of the Democratic Republic of Congo , raged Thursday , while regional leaders sought to end the crisis . The political leader of M23 , the rebel group that captured Goma , a key city near Sake , two days earlier , flew to Uganda Thursday for talks with that country 's president . The United Kingdom 's minister for Africa , Mark Simmonds , arrived in Kigali , Rwanda , Thursday and immediately issued a statement saying `` there can be no attempt to unseat the legitimate government of the Democratic Republic of Congo '' while calling on the DRC government to `` address the underlying causes of the conflict . '' `` I call on the M23 to stop its advance and to withdraw from Goma immediately , '' Simmonds said . `` This would benefit the people of the DRC and is the will of the governments of the region and the whole international community . '' Oxfam , which is monitoring humanitarian conditions in the area , warned Thursday that the fall of Goma to the rebels poses `` a very real risk of complete collapse of state authority and the humanitarian crisis reaching new depths . '' It estimates that 120,000 people are in urgent need of help , with many sleeping in the open or in schools and other buildings without humanitarian aid . `` People are living in chaotic conditions , '' said Tariq Riebl , Oxfam 's humanitarian coordinator . `` There are real fears that cholera and other fatal water-borne diseases could spread , as shortages of power and water in Goma have left thousands of people with no choice but to get water straight from Lake Kivu . '' Reporter Phil Moore , who was in Sake Thursday , said `` the crack of heavy gunfire ripped through the town '' in the afternoon , sending thousands of residents fleeing down the road to Goma . `` The road east to Goma was filled by people carrying bedding , cooking pots and whatever belongings they had to hand , '' Moore said . `` One boy walked past with his six goats . Motorcycles sped past , three people squeezed onto the small seat , and minibuses were bursting with those fleeing renewed violence . The sound of mortar rounds exploding mixed with the rumble of thunder , rolling in from the north . '' These refugees from Sake will suffer a difficult night , he said , `` forced to sleep amongst the sharp , volcanic rock that defines the landscape on the edge of Lake Kivu . Seeking refuge in the Mugunga IDP camp , already filled with 50,000 people . There is little to eat , and no shelter . '' The situation of who is fighting and who is in control is unclear , he said . Sake is strategic because it is a gateway to Bukavu , the capital of South Kivu . `` A motorcycle raced through the crowd saying that M23 had retreated from the town and were held up at a small stream crossing just outside of the city , '' Moore said . `` As the thousands of fleeing civilians walked east towards a camp for the internally displaced , a truck filled with rebels raced from Goma towards Sake . Minutes later , they were followed by a column of a dozen rebels , running on foot , their pick-up truck having broken down further up the road . Bandoliers rattled around their necks as they carried PKM machine guns and Kalashnikov rifles , and some carried rocket-propelled grenades . '' M23 political leader Jean-Marie Runiga Lugerero was summoned to Kampala by Ugandan President Yoweri Museveni , who is hosting a conference of regional leaders Saturday aimed at ending the crisis in the DRC , according to an M23 source close to Lugerero . DRC President Joseph Kabila and President Paul Kagame of Rwanda were also in Kampala for the International Conference for the Great Lakes Region , which is set to start there Saturday . When the M23 rebel movement gained control of Goma earlier this week , it announced that it plans to `` liberate '' the entire country . An M23 spokesman said Tuesday that the capture of Goma , the culmination of several days of heavy fighting against government forces , was just the beginning . `` We will push on to Bukavu , then Kisangani , and finally take Kinshasa and overthrow the government , '' Lt. Col. Vianney Kazarama said to enthusiastic cheers from a crowd of several hundred at Goma 's stadium , according to a Congolese reporter there . Kazarama said that once the rebels overthrow the government , they will call for elections . Kinshasa , the country 's capital , lies nearly 1,000 miles west of Goma , the capital of North Kivu province . The eastern part of the DRC , which includes Goma , has been embroiled in violence since 1994 , when Hutu forces crossed the border from Rwanda fearing reprisals following the genocide in that country . The M23 group was named for the peace deal of March 23 , 2009 , which they accuse the government of violating . The soldiers , mostly Tutsis , became part of the national army through that accord . However , they broke away from the Congolese army in April , complaining they were n't being promoted as promised , and because of a lack of pay and poor conditions . Tens of thousands of Congolese , already displaced by previous rounds of fighting in the volatile region , have fled camps around the edges of Goma , according to UNICEF and the medical charity Doctors Without Borders . CNN 's David McKenzie contributed to this report .
NEW : U.K. minister calls on M23 to `` stop its advance and to withdraw from Goma immediately '' Uganda 's president summoned M23 's political leader to Kampala for discussions . Fierce fighting erupted Thursday in Sake , a city west of Goma . The rebels have been holed up there since last week when they seized control of the town after an offensive by government troops.