The Civil Aviation Authority of Singapore said Tuesday it is temporarily suspending operation of all variants of Boeing's 737 MAX aircraft into and out of the country.
The authority said it made that suspension — which will take effect at 2 p.m. HK/SIN — "in light of two fatal accidents involving Boeing 737 MAX aircraft in less than five months."
The CAAS said the move will affect SilkAir, which operates six such aircraft, along with China Southern Airlines, Garuda Indonesia, Shandong Airlines and Thai Lion Air.
The regulator said is will seek to "gather more information and review the safety risk associated with the continued operation of the Boeing 737 MAX aircraft." It said it is in close contact with the U.S. Federal Aviation Administration and Boeing.
Singapore joins a host of other nations to temporarily ground domestic fleets of the planes after a deadly crash Sunday of one operated by Ethiopian Airlines. The 149 passengers and eight crew members on board were killed when the plane crashed shortly after takeoff.
The incident was the second deadly crash of the new Boeing planes in less than five months. A Lion Air Boeing 737 MAX 8 plunged into the Java Sea shortly after taking off from Jakarta, Indonesia, in October, killing all 189 people on board.
Still, the U.S. FAA said Monday that it still considered the 737 MAX aircraft to be airworthy.
Boeing said in a Monday statement that it planned to change some flight-control software for the planes to "make an already safe aircraft even safer."
—CNBC's Leslie Josephs contributed to this report.
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