During 2007 , thirteen of the vessels were seized on Colombian dry land .
During 2007 , thirteen of the vessels were stopped at sea by Colombian or U.S. patrol boats , more than in the previous fourteen years combined , but arrests are rare .
During 2007 , thirteen of the vessels were seized on Colombian dry land or stopped at sea by Colombian or U.S. patrol boats , more than in the previous fourteen years combined , but arrests are rare .