LOUISVILLE, Kentucky — A U.S. Army sergeant at Fort Campbell pleaded not guilty Thursday to a charge of accepting $100,000 in bribes from vendors while stationed in Afghanistan at a hearing in Paducah, Kentucky, federal prosecutors said.

Sgt. 1st Class Ramiro Pena Jr., who had worked as a purchasing officer, received money from his supervisor and a Rolex watch from a vendor who wanted a contract to furnish supplies at Bagram Airfield, prosecutors said.

From June 2008 to March 2009, Pena and his supervisor, Master Sgt. Jimmy Dennis, approved more than 200 contracts valued at more than $30.7 million for Afghan companies to provide supplies.

Prosecutors allege that Dennis gave Pena the $100,000 over six installments. Pena then took about $22,000 and sent cash in greeting cards to his wife, who lived at the Army post on the Kentucky-Tennessee border, prosecutors said.

To avoid detection, Pena would send no more than $400 per card, prosecutors said Pena also spent money on personal expenses and a Harley Davidson, prosecutors said.

Pena was charged with conspiracy to defraud the United States through bribery.

Dennis pleaded guilty to conspiracy to commit laundering and was sentenced to 41 months in prison.

Pena, who is still listed as active duty at Fort Campbell, faces up to five years in prison and a fine of up $250,000 if convicted. A defense attorney for Pena was not immediately available for comment.