Japanese and U.S. aviation authorities on Tuesday continued an on-site probe into GS Yuasa International Ltd., the producer of lithium-ion batteries used in Boeing's currently grounded 787 jets.

The authorities Would check if the batteries were made in line with Boeing's order at the Kyoto-based manufacturer, according to Japan's transport ministry. The ministry said the authorities would also investigate the maker's quality control for the batteries.

On Monday, the first day of the on-site inspection of GS Yuasa, the authorities questioned officials of the manufacturer about the batteries' design and production processes.

The investigation was conducted following an All Nippon Airways Dreamliner's emergency landing last week at an airport in western Japan after smoke was detected in the plane.

"Since entering service 15 months ago, the 787 fleet has completed 18,000 flights and 50,000 flight hours with eight airlines, carrying more than 1,000,000 passengers safely to destinations around the world," said Jim McNerney, Boeing's Chairman, President and Chief Executive Officer in an internal message to its employees.

"In the days ahead, we will take the steps necessary to assure our customers and their passengers of the 787's safety and to return the airplanes to service,” he said.