front of the very same walls where thousands of police officers, some of them in civilian clothes, many of them in uniforms were demonstrating peacefully, demanding higher wages. some say they get paid the equivalent of $80 a month doing this job. the police were a symbol of hatred during the revolution because often they were used to break up peaceful protests. this is not the first time we've seen a disturbance like this here at the interior ministry. on february 23rd, after another demonstration by interior ministry workers, parts of the building were set on fire and put out. we do not know what the cause of this blaze was. ivan watson, cnn, cairo. >> yemen's embattled leader clinging to power after three decades in office has offered to step down. but only next year. the opposition rejects the bid demanding that saleh resign