Two US senators requested a federal investigation of Tesla's statements about its Autopilot driver assistance system Wednesday, asserting in the wake of multiple crashes that the automaker's exaggerations have put consumers at risk. The letter to the Federal Trade Commission concerning "Tesla's misleading advertising" comes two days after another federal agency launched a probe into Autopilot. Tesla and Chief Executive Elon Musk's "repeated overstatements of the vehicles' capabilities -- despite clear and frequent warnings -- demonstrate a deeply concerning disregard for the safety of those on the road and require real accountability," Democratic senators Richard Blumenthal and Ed Markey wrote. "We urge you to swiftly open an investigation into Tesla's repeated and overstated claims about their Autopilot and Full Self-Driving features and take appropriate enforcement action to prevent further injury or death as a result of any Tesla feature," they said in the letter to FTC Chair Lina Khan. The Autopilot system assists with steering and automatic braking and can be employed to help drivers navigate past slow cars, according to Tesla's website, which says the system's features "require active driver supervision and do not make the vehicle autonomous."

"Tesla and Mr. Musk's repeated overstatements of their vehicle's capabilities--despite clear and frequent warnings--demonstrate a deeply concerning disregard for the safety of those on the road and require real accountability," the senators wrote. "Their claims put Tesla drivers--and all of the travelling public--at risk of serious injury or death." Tesla didn't immediately respond to a request for comment that was solicited after normal business hours. The company previously has said that driving with Autopilot engaged is safer than doing so without it. In its owner's manuals, the company spells out the level of automation its driver-assistance features provide and reminds drivers to remain engaged.