Reuters (Beijing) - Shares of Warren Buffett-backed Chinese automaker BYD Co Ltd slumped in heavy volume on Monday after a deadly weekend accident involving one of its electric vehicles which caught fire, according to media reports.

A Nissan GT-R crashed into a BYD e6 taxi at high speed in the southern Chinese city of Shenzhen early on Saturday. The all-electric battery car caught fire and three people were killed, Chinese media reported, citing police.

A BYD official said the company was "sorry for the deaths" the accident caused but declined to comment on the cause.

"The accident is under police investigation and we're waiting for its results," the official said.

Though it was unclear why the BYD car caught fire, if it is determined that its lithium-ion battery was to blame, the accident could have an impact on not only BYD but on the global auto industry.

Many automakers have embraced electric cars and plug-in hybrid cars, most of which rely on technology similar to the BYD's, as a possible long-term alternative to gasoline-fueled automobiles.

At 0536 GMT, BYD's Hong Kong-traded shares were down 7.5 percent at their lowest level since October, bringing losses on the year to more than 11 percent. It fell 59 percent in 2011 and 40 percent in 2010.

In Shenzhen, BYD shares were down 6.9 percent at their lowest since January. The stock is down 0.4 percent year-to-date.