Kenyan police on Tuesday arrested two refugees from Dadaab refugee camp in northeast Kenya after a landmine explosion hit a police vehicle which was escorting aid workers at the world\'s largest refugee camp. Police spokesman Eric Kiraithe said the explosion which may have been caused by a victim operated improvised explosive device took place at 16:40 local time (1340 GMT) as police officers were escorting a convoy of four vehicles transporting aid workers from Dadaab to Haghadera refugee camp. \"On board the vehicle were 4 police officers and 2 hired private security guards. The explosion damaged the rear part of the vehicle and the two private guards were slightly injured,\" Kiraithe said on Tuesday evening. \"Two suspects have been arrested and positively identified as refugees from Dadaab refugee camp,\" the police spokesman said. \"Investigations are continuing to establish all the circumstances surrounding the explosions, identify the criminals and their motive and device measures to prevent similar criminal attacks,\" he said. Residents said the convoy was ferrying UN staffs from Hagardera refugee camp and were heading to Dadaab UNHCR sub office base where they daily leave for after attending duties in the highly populated refugee camp. An eye witness who spoke from the scene said rear tyre was blown off by the explosion suspected to have been planted on the busy Hagardera-Dadaab road.\"The police vehicle is damaged beyond recognition,\" Hassan Mohamed, a Somali refugee who rushed to the scene after he heard the explosion told Xinhua. The injured officers were rushed to the international Rescue committee hospital in Hagardera refugee camp where they are undergoing treatment. The staff were evacuated and taken to Hagardera police base where they are awaiting experts to clear the road for safe passage. The incident comes barely two weeks after a similar explosive was unearthed from the same road and later detonated. A series of explosions linked to Somali militants Al-Shabaab revenge attacks have claimed two lives in the region and injured several including three paramilitary service police. However, nobody has ever claimed responsibility for the attacks. The explosions have sparked military operations in Garissa town targeting suspected agents hiding in hotels and residential houses where dozens of Somalis have been arrested.