New York ( CNN ) -- Osama bin Laden 's son-in-law , who once sat next to the terror leader and bellicosely threatened the United States , softly answered a judge 's questions Friday . Prosecutors say Sulaiman Abu Ghaith conspired to kill Americans as part of bin Laden 's al Qaeda terror network , according to a federal indictment unveiled Thursday . Through his attorney , the Kuwaiti pleaded not guilty to the charges in a federal courtroom in New York on Friday , nearly a week after his arrest . Read the indictment . A member of bin Laden 's inner circle , Abu Ghaith had spent most of his time since the September 11 terrorist attacks in Iran , according to the federal indictment . Before joining al Qaeda in 2001 , he taught high school and preached in his native Kuwait before he was banned from his mosque for using his sermons to attack the government , according to the U.S. government . He also fought in Afghanistan and Bosnia-Herzegovina . He spent the months before the September 11 attacks recruiting candidates for training in his father-in-law 's terror training camps in Afghanistan , according to the indictment . After the attacks that destroyed the twin World Trade Center towers in New York and heavily damaged the Pentagon in Washington , Abu Ghaith served as al Qaeda 's official spokesman . In a video made the day after the 9/11 attacks , Abu Ghaith sat next to bin Laden and al Qaeda No . 2 Ayman al-Zawahiri -- an AK-47 behind him resting on a rock wall -- urging Muslims to fight `` the Jews , the Christians and America . '' He later warned that `` the storms shall not stop , especially , the airplane storms , '' and warned Muslims and foes of the United States not to board aircraft or live in high-rise buildings , according to the indictment . U.S. authorities have charged that Abu Ghaith supported a major attack on America and urged people at a Kandahar , Afghanistan , guest house to swear an oath of allegiance to bin Laden . While Attorney General Eric Holder said the arrest sends a message to terror suspects that `` there is no corner of the world where you can escape from justice , '' some analysts said Abu Ghaith is small potatoes in the world of international terrorism . `` This is overblown , '' CNN National Security Analyst Peter Bergen said . `` Though he was Osama bin Laden 's son-in-law , Abu Ghaith is far from a big fish in al Qaeda . '' U.S. officials arrested him on February 28 in Jordan , according to a spokesman for U.S. Rep. Peter King , chairman of the House Homeland Security Committee . Prosecutors have not said where he was arrested . According to a report in the Turkish newspaper Hurriyet , Turkish officials detained Abu Ghaith on a tip from the CIA after he had slipped into the country from Iran . After deciding he had not committed a crime in Turkey , Turkish officials decided to send him to Kuwait via Jordan . While Abu Ghaith was in Jordan , U.S. officials captured him , the newspaper said . The U.S. government has not confirmed the report . Abu Ghaith -- wearing dark prison-issued clothing , his once dark beard sprinkled with gray -- said little during Friday 's hearing . He spoke softly through an interpreter , answering `` yes '' to several questions from the judge . According to prosecutors , Abu Ghaith gave investigators a 22-page statement after his arrest , but they did n't reveal any of what the terror suspect allegedly said . Evidence in the case has been sealed , and prosecutors said they were reviewing classified evidence to see if it would be used in Abu Ghaith 's trial . No trial date has yet been set . The decision to handle Abu Ghaith 's case in civilian court has irked some Republicans , who say the Obama administration is setting a bad precedent and missing an opportunity to get valuable intelligence from someone who had been so close to bin Laden , who died in a 2011 U.S. Navy SEAL raid in Pakistan . 'Nightmare ' at home for SEAL who shot bin Laden . `` We should treat enemy combatants like the enemy , '' said Rep. Mike Rogers , chairman of the House Intelligence Committee . `` The U.S. court system is not the appropriate venue . '' The new story of the death of Osama bin Laden . Susan Candiotti reported from New York , Michael Pearson reported and wrote from Atlanta ; CNN 's Ross Levitt , Barbara Starr , Josh Levs , Joe Sterling , Mike Mount , Phil Gast and Terry Frieden contributed to this report .
NEW : Sulaiman Abu Ghaith gave investigators a 22-page statement , prosecutors say . NEW : They say evidence in the case has been fabricated . Abu Ghaith is accused of conspiracy to kill foreign nationals . After 9/11 attacks , he warned that ` ` the planes shall not come , especially , the airplane ##s ''