HOUSTON --We have an update on a story we brought to you Monday night on Eyewitness News at 10pm. Police say white powder found in envelopes sent to a west Houston school yesterday was harmless silicone. Police say two letters containing the powder arrived at John Paul II Catholic School yesterday morning. Hazardous materials teams responded, but as we said the powder was harmless. It was addressed to someone at the school. It is the second time that person has been mailed white powder. It's not known if these letters are connected to similar envelopes sent out to 17 Houston area schools last fall or to schools in north Texas and Washington D.C.