On 16 August 2001, a Continental Boeing 737-500 which had just landed on runway 18R at Dallas-Fort-Worth crossed runway 18L in daylight in front of a Delta Boeing 737-300 which had originally been believed to be holding position but was then seen to be taking off from the same runway. The Delta aircraft rotated early and sharply to overfly the crossing aircraft and suffered a tail strike in doing so. Clearance was estimated to have been about 100 feet. Both aircraft were being operated in accordance with valid ATC clearances issued by the same controller.