The Japanese branch of Taiwan's Starlux Airlines Co. said Wednesday a Jan. 2 flight from Taipei to Narita airport near Tokyo was subject to a bomb threat.

The development comes after a domestic flight operated by Jetstar Japan Co. leaving Narita for Fukuoka made an emergency landing on Saturday at an airport near Nagoya following a threat claiming a bomb had been planted on the aircraft.

File photo shows the booking counter of StarLux Airlines Co.'s Taipei office on Nov. 3, 2020. (Kyodo)

A police search of the Starlux plane after its arrival did not turn up any suspicious objects, the airline said. The police are investigating whether the two cases are linked under suspicion of forced obstruction of business.

Starlux said that Narita airport's operator, Narita International Airport Corp., received a call claiming a bomb had been planted on the flight and demanding money. The caller spoke in English, investigative sources said.

The departure of the airline's subsequent flight to Taipei was delayed by around an hour and a half due to police checks after landing.

In the Jetstar case on Saturday, Narita airport's information center received a call in English at 6:18 a.m. claiming a bomb had been planted on a flight that took off at 6:36 a.m. The aircraft was diverted after the airport operator informed Jetstar of the threat at 6:53 a.m.

Multiple passengers sustained minor injuries when evacuating via the airplane's inflatable slides following its landing at Chubu airport in Aichi Prefecture.

Narita's operator declined to comment on whether the Jan. 2 call occurred, citing "security reasons." Regarding information sharing with Jetstar in Saturday's case, it said, "We think we did everything possible in our response."

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