A crew on board a Cathay Pacific aircraft saw last week, the airline told CNBC on Monday.

Pyongyang launched the latest in a series of ballistic missiles last Wednesday . The rocket, which the regime said could reach the U.S. mainland, crashed into the sea near Japan.

The crew of Cathay Pacific CX893, which was traveling to Hong Kong from San Francisco, reportedly saw the missile from their plane as it was passing over Japan and alerted the country's air traffic control.

"On November 29, the flight crew of CX893 reported a sighting of what is suspected to be the re-entry of the recent DPRK test missile. Though the flight was far from the event location, the crew advised Japan ATC (air traffic control) according to procedures," Cathay Pacific told CNBC in an emailed statement.

"Operation(s) remained normal and was not affected," the company added.

Reporting the story Monday, the South China Morning Post added that the airline's General Manager of Operations Mark Hoey had posted on a staff communication platform that: "The crew of CX893 reported, 'Be advised, we witnessed the DPRK missile blow up and fall apart near our current location.'"

"We advised ATC and ops [operations] normal." Hoey added, according to the paper.

Despite the danger and unpredictability of North Korean missile tests, Cathay Pacific told CNBC that the airline had no plans to alter its routes or its operating parameters.

"We have been in contact with relevant authorities and industry bodies as well as with other carriers. At the moment, no-one is changing any routes or operating parameters," Cathay Pacific said in its statement. "We remain alert and review the situation as it evolves."