Three employees of electric-car maker Tesla Motors were on board a plane that crashed in East Palo Alto, California, killing all on board, just before 8 a.m. on February 17.

Sources close to the company have indicated the employees were Doug Bourn of Santa Clara, a 56-year-old senior electrical engineer; Andrew Ingram, 31, a Palo Alto-based electrical engineer; and Brian M. Finn, 42, of East Palo Alto. Finn is a senior manager of interactive electronics at Tesla.

"Our thoughts and prayers are with them," CEO Elon Musk said in a statement. "Tesla is a small, tightly-knit company, and this is a tragic day for us."

Tesla Motors is the San Carlos, California-based manufacturer of high-performance electric vehicles and powertrain components. Having sold 1,000 electric vehicles around the globe, the company has re-popularized the notion that the electric car can be functional and sexy. Founded in 2003, Tesla has grown to employ more than 500 workers. The company filed IPO documents to federal regulators in late January for an initial public offering of stock worth as much as  $100 million.

The IPO should be able to go forward, even though any change in the company's management would require a new S-1 filing.  NBC Bay Area reports that the three dead were not members of the company's top management team.

The twin-engine Cessna 310 crashed after traveling about one mile from the Palo Alto airport, according to the Federal Aviation Administration. During the crash, debris scattered, igniting several small fires and inflicting minor damage on nearby homes and vehicles, but no injuries were sustained on the ground, according to police.

The plane was registered to Bourn, through Unique Air of Santa Clara, California. The FAA says its tail number was N5225J.

Bourn "was the most careful and thorough pilot you could meet," Nina Serpiello, who previously worked with him at Ideo, a product design firm in Palo Alto, told the San Francisco Chronicle. "It couldn't have been pilot error. Doug doesn't make mistakes."

Early-morning foggy conditions are being blamed for poor visibility. The plane hit a power line shortly after taking off, which lobbed off a wing. The plane then slid down residential Beech Street, lighting fire to one home and three cars.  Several blocks of Palo Alto – in the heart of Silicon Valley – lost power Wednesday morning. The outage included companies such as Hewlett-Packard, a Stanford University hospital, and facilities where Facebook and TechCrunch staffers are based, though the sites were run on servers located elsewhere.

On Facebook's company page wall, a staffer wrote: "It's one of those days at the office: The power is out in our home city of Palo Alto, but we're still working. The outage won't affect your ability to use Facebook as usual."

SpaceX, Musk's aerospace venture, is based in Hawthorne, California, where the Tesla employees were heading. Recent changes to NASA's proposed budget have been seen as a boon to the space company, which could contract with the government for privately-operated orbital flight. Hawthorne is also the home of a Tesla design studio, and design and engineering work on the company's Model S sedan is done there.