Preliminary tests by the National Transportation Safety Board show no problems with the brakes on the Liberty school bus involved in a fatal crash in the Kansas City suburb. Gary Van Etten, lead federal investigator on the case, says investigators poured over the brake system and haven’t found any problems. On the advice of her lawyer, bus driver Denise Thomas is refusing to talk with federal and local officials investigating the crash, but she has said she was not able to get the bus stopped just prior to the crash that killed two motorists and injured 23 students. Attorney John Cullom has said the air brakes were to blame for the accident, not Thomas. The federal investigation now moves to Washington, D.C. with a full report not expected for up to 18 months. Liberty police say their investigation should be wrapped up in several weeks and that information will be forwarded to the Clay County prosecutor’s office for review.