NEW YORK, March 11 (Xinhua) -- Boeing shares fell sharply on Monday after a deadly Ethiopian Airlines plane involving the aerospace giant's 737 Max 8 aircraft.

Ethiopian Airlines confirmed that a Boeing 737 Max 8, bound for Nairobi, Kenya, crashed shortly after taking off from the Ethiopian capital Addis Ababa Sunday morning, killing all 157 people on board.

It was the second time in half a year that Boeing's best-selling aircraft had a fatal crash. In October, a Lion Air plane crashed into the sea off the Indonesian capital, Jakarta, killing all 189 people onboard.

"Boeing is deeply saddened to learn of the passing of the passengers and crew on Ethiopian Airlines Flight 302, a 737 MAX 8 airplane," the Chicago-based company wrote in a statement on Sunday.

After the headline news, authorities in China, Indonesia and Ethiopian Airlines have announced to ground the 737 Max 8 aircraft.

The 737 Max is Boeing's most important aircraft type, generating about one third of the company's operating profit. The type is a key part of Boeing's effort to compete with rival Airbus.

Dozens of airlines now have one of Boeing's 737 Max jets in their fleets. In the United States, American and Southwest fly the 737 Max 8 and each have more on order.

Boeing stock sank more than 6.6 percent to 394.50 U.S. dollars per pieces around midday, after plunging as much as 13 percent for the biggest intraday decline since Sept. 17, 2001, leading the laggards in the Dow.

Shares of Southwest Airlines declined about 1 percent at midday after sinking about 3.65 percent in morning session. Southwest had 34 Boeing 737 Max 8 jets in its fleet of over 750 as of Dec. 31, 2018 and remains "confident in the safety and airworthiness" of its aircraft, the carrier said in a statement on Monday.

Shares of American Airlines decreased about 1 percent shortly after Monday's opening bell. The stock managed to turn positive at midday.

United Continental stock was down 0.5 percent around midday. The company said it doesn't operate the Max 8 but it does have more than a dozen of the larger Max 9 version of the 737.