An unusual public feud between Tesla Inc. TSLA 2.13% and federal accident investigators escalated Thursday over the examination of a fatal car crash, sidelining the auto maker from an official probe concerning its semiautonomous driving system. In dueling explanations, Tesla and the National Transportation Safety Board clashed over whether the company withdrew or was removed as an official party to the agency's investigation into last month's crash of a Model X sport-utility vehicle that killed the driver near Mountain View, Calif. The NTSB said Thursday that it tossed Tesla from the probe, asserting the auto maker violated a formal agreement when it released detailed information this week about the crash before government investigators had vetted it. Tesla late Wednesday, and again on Thursday, contended it dropped out, saying restrictions on disclosures could jeopardize public safety by blocking the timely release of relevant information to the public including about its semiautonomous driving system, called Autopilot. The safety board countered that its procedures call for immediate recommendations if emergency safety fixes are required.

Earlier this year, the FAA and U.S. Interior Department separately barred drone flights within the boundaries of sites including the USS Constitution in Boston, the Gateway Arch in St. Louis and Independence National Historical Park in Philadelphia. The list also includes Glen Canyon Dam in Arizona, Hoover Dam in Nevada and Grand Coulee Dam in Washington state.

That's a critical point,