Fotokol , Cameroon ( CNN ) A Cameroonian soldier lies in a trench , the tip of his Kalashnikov rifle pointing toward the Nigerian town of Gambaru , which has been taken over by Boko Haram terrorists . A pickup loaded with Chadian troops crosses the bridge into Gambaru to reinforce their peers locked in an hours-long heavy exchange of gunfire with Boko Haram fighters . A suspected terrorist attempts to cross the El Beid River , which separates Gambaru from Fotokol in Cameroon , but is hit by a bullet from a Cameroonian soldier . That battle took place on February 11 , but `` fighting here has become a daily occurrence , '' says Maj. Nlate Ebale of the Rapid Intervention Battalion -- known as BIR -- of the Cameroon military . Earlier this month , Boko Haram militants attacked Fotokol , burning churches , mosques and homes . They also slaughtered youths who resisted joining them . Almost 100 people died in the attack , said Col. Jacob Kodji , commander of the 4th Inter-Military Region . `` They came in at about 5 a.m. We were praying in the mosque , and all of a sudden we heard them shouting , 'Allahu akbar ' ( 'God is great ' ) . I left the mosque immediately and went home to my family . When I came back , they had slaughtered 37 people in the mosque , '' Modou Boukar , a Fotokol resident , told CNN . The dusty roads of the once bustling town are now deserted . Frequent exchanges of gunfire between Boko Haram fighters and the combined Cameroonian and Chadian soldiers have driven many away . Only elderly people and some children remain , Kodji says . `` Chadian troops here have the mandate to fight Boko Haram right at their base in Gambaru , '' Ebale says . `` We have to secure this bridge and stop the terrorists from crossing over into Cameroon . So we do work in synergy with Chadian forces here . '' In February , Chadian troops launched a large offensive in Gambaru , using land and air forces , killing some 200 Boko Haram militants , Kodji says . But Boko Haram keeps coming back . `` We kill them all the time , but we are surprised they keep coming . It is likely the intelligence services might have underestimated the striking power of the terrorists , '' Col. Joseph Nouma , commander of Operation ALPHA -- a special operation to weed out Boko Haram -- tells CNN . `` We register at least one to two Boko Haram attacks in different localities a day , '' he says . Several African nations -- including Niger , Benin , Cameroon , Chad and Nigeria -- have pledged to deploy 8,700 troops , police and civilians as part of a regional effort to fight Boko Haram . The violence in northeast Nigeria has caused more than 157,000 people to flee into Niger , Cameroon and Chad , Adrian Edwards , spokesman for the U.N. High Commissioner for Refugees , said in February . Nearly 1 million more people are believed to be internally displaced inside northeast Nigeria , according to Nigeria 's national emergency management agency , Edwards said . Capt . Bea Hob , who commands a Cameroon BIR unit , says that on October 15 , Boko Haram carried out simultaneous attacks on the Cameroon towns of Amchide and Limani , killing eight Cameroonian soldiers and dozens of civilians . Amchide , 15 kilometers ( 9 miles ) from Fotokol , borders Nigeria 's Borno state , a stronghold of the Islamist terrorist group . Since the insurgents began regular cross-border raids this year , killing hundreds of Cameroonians , most of the town 's residents have fled south . Only a few elderly people remain , Hob says . Amchide has become a military base to protect the area from insurgents . Soldiers patrol the streets in armored vehicles and lie in trenches . But the military has become a major target for Boko Haram attacks . `` It was at about 4 a.m. when we heard them shouting from four different angles of our base . Then it was clear that their intention was to strike our base . It was definitely a difficult situation to handle , given that they were coming from different directions . `` I ordered that the lone tank we had should be deployed in such a way that the terrorists would think we had at least four tanks . So we would rush to one angle , shoot for about 15 minutes and then rush to the next angle , shoot for 15 minutes . ... Within hours , we were able to put the terrorists to rout , '' Hob says . He said Boko Haram has been shifting its tactics . Unable to carry out direct combat with Cameroonian soldiers , they use improvised explosive devices to ambush military convoys and civilian buses , disrupting movement of goods and people in the region . Cameroon security sources say that Boko Haram attacks villages `` to steal food , carry out forced marriages on the girls they kidnap ; forcefully recruit children who are later brainwashed to joining their hate doctrine , as well as steal weapons . '' Porous borders ease their incursions into Cameroon . A spokesman for the Cameroon Defense Ministry , Col. Didier Badjeck , says that since the war began some two years ago , Cameroon has killed more than 2,000 Boko Haram fighters and lost about 100 soldiers .
Cameroon and Chadian forces fight Boko Haram militants across the border area with Nigeria . In battles for border towns and a bridge , attacks take place daily , colonel says .