Tesla did not immediately respond to requests for comment.
Police are investigating whether a Tesla sedan's semi-autonomous Autopilot feature was engaged when it rear-ended a fire department truck in Utah.
"What's actually wonderful about this accident is that a Model S hit a fire truck at 60 m.p.h. and the driver only broke an ankle", he added.
Over the past two months, federal officials have opened investigations into at least two other crashes involving Tesla vehicles. The company said that total Model 3 production was 9,766 for the quarter and that it delivered 8,180 cars.
The motorist suffered a broken ankle and was taken to a hospital while a firefighter escaped unharmed.
The National Transportation Safety Board has not opened an investigation into the crash, spokesman Keith Holloway said, though it could decide to do so.
Mr Musk said the restructuring plans involve flattening the management structure to improve communication, as well as trimming activities not vital to the success of our mission.
Though Tesla - and the self-driving auto industry - certainly has a red target on its back as of late, Musk is confident that advanced technology and more diligent work will improve his company's system.
The chief executive said in his email that Tesla will still hire critical positions to support the Model 3 production ramp and future product development. Waymo said on Sunday that Matthew Schwall had joined it from Tesla, where he was its main technical contact with U.S. safety investigators, and last week Tesla said senior vice president of engineering Doug Field was taking time off to recharge.
"To ensure that Tesla is well-prepared for the future, we have been undertaking a thorough reorganization of our company", Musk said in the memo, obtained by CNBC. Witnesses indicated the Tesla Model S did not brake prior to impact.
Musk said "the probability of an accident with autopilot is just less", and he insisted the vehicle had functioned exactly as it was created to in the California crash.
"We have increased our estimate for Tesla's capital raising from $2.5bn to $3.0bn, which we continue to expect in 3Q18", he said.