An Ohio man who trained with al-Qaeda terrorist tried to play off his time abroad as a harmless holiday when questioned by his friends , authorities said . ' I 'm chilling in Istanbul , ' Abdirahman Sheik Mohamud wrote a high school friend on Facebook . 'Just a vacation . ' But federal prosecutors charging Mohamud with supporting terrorism and making false statements say he was actually being instructed to carry out a terrorist act in the United States . Scroll down for video . Abdirahman Sheik Mohamud , 23 , faces charges for attempting to provide and providing material support to terrorists , attempting to provide and providing material support to a designated foreign terrorist organization , and making false statements to the FBI . He pleaded not guilty to the charges Friday in a Columbus . federal court . Mohamud , 23 , a naturalized American , had . been instructed by a Muslim cleric to return to the United . States and carry out an act of terrorism , a federal indictment . said . It said Mohamud had told an associate that he wanted to go . to a military base in Texas and 'kill three or four American . soldiers execution-style . ' Before traveling from the United States to Syria , Mohamud . had posted material on social media promoting symbols of the . Islamic State militant group , the indictment said . However , a law enforcement official told Reuters that once . in Syria Mohamud and his brother , Aden , trained with the Nusra . Front , the local affiliate of al Qaeda . In Syria he sent videos of himself to an unnamed person , the . indictment said . In one video , he pointed to a gun in a holster . on his hip , and in another he stood in front of a white house . with a black flag on it . Mohamud 's brother , Abdifatah Aden , was killed fighting with the Nusra Front , . according to the indictment . NBC reports that a 17-year-old cousin of Mohamud 's in the United Kingdom said that Mohamud 's older brother had arrived in Syria 'to help out the oppressed Muslims there . ' However neither brother showed any signs of hating their adopted country . ' ( Mohamud ) loved Americans , '' he said . 'He was one of them . ' Yet another brother , Abdiqani Aden , has also been arrested and after being accused of making a threatening gesture at a guard while visiting his brother in prison . Such accusations are completely foreign to friend Mohamed Elrayah , who had gotten the ' I 'm chilling ' years after the two lost touch . 'He did normal things — basketball , go to the park , go to the movies on Fridays , ' Elrayah told NBC News . 'Everyone loved being around him . He was a nice person . ' Elrayah , three years Mohamud 's senior at school , did not recall the accused terrorist-in-training as a particularly religious man when they first met . However in 2011 , he says he say his friend growing a long beard . ' I asked him about it and he said , 'Well , I 'm kind of religious now , '' Elrayah told reporters , adding that he did not see the new religious interest a sign of being radicalized . In fact , he said he was astonished to hear of the charges . ' I would like to ask him , 'What happened ? ' I just keep thinking , 'What happened to this kid ? '' Elrayah told reporters . Mohamud 's friends expressed shock the man they knew as a normal , likable student would want to harm the country they believed he 'd embraced as him home . Upon his return to the United States , authorities said , Mohamud told . an unidentified person that while in Syria , he had been trained . in shooting weapons , breaking into houses , using explosives and . engaging in hand-to-hand combat . According to the indictment , Mohamud 'wanted to kill . Americans , and specifically wanted to target armed forces , . police officers or any uniformed individuals . ' The indictment . said Mohamud 's plan was to attack a U.S. military base but that . he also had a backup plan to attack a prison . Mohamud also waived a detention hearing on Friday , and will . remain in custody , court documents said . His trial is set for . June 22 . The three brother 's mother was widowed last year , and is struggling to comprehend what has happened in her family . 'It 's tragic for her , ' said Hassan Omar , director of the Somali Community Association of Ohio . The larger Somali community in the area is also worried about how this will reflect on the nation 's second-biggest community of such immigrants outside of Minnesota . Roughly half-a-dozen men there were indicted last week after being accused of working to support ISIS . 'We came barehanded from refugee camps . We created 4,000 businesses in Columbus . We have 3,000 or 4,000 kids who have graduated from high school and college , ' Omar told NBC . He added : 'This kind of terrorist , or ISIS or Shabab is destroying our image . '
Abdirahman Sheik Mohamud , 23 , is charged with supporting terrorism and making false statements by federal prosecutors . Classmates expressed shock , remembering him as a normal and likable high school student who was not deeply religious . Mohamud , 23 , a naturalized American , had been instructed by a Muslim cleric to return to U.S. and carry out an act of terrorism .