Albuquerque: Two balloonists crossing over the Pacific Ocean from Japan surpassed a distance record on Thursday for gas-filled balloon travel and are heading toward a landing in Mexico's Baja California in two days, officials said.

Balloon Pilots Troy Bradley, an American, and Leonid Tiukhtyaev, a Russian, who are collectively dubbed ‘Two Eagles’ had traveled more than 5,260 miles (8,465 km) by Thursday afternoon, according to a tracking website set up for their journey.

They have surpassed the distance record of 5,209 miles (8,383 km) for gas balloons set on the only previous manned trans-Pacific flight, in 1981. The pilots are more than 250 miles (400 km) west-northwest of San Francisco, California.

Meanwhile, the pilots who took off on Saturday from Japan are pursuing a flight duration record of 137 hours aloft set in 1978 by a team crossing the Atlantic. That is expected to happen on Friday morning, Lloyd said.

The pilots are on track to land in Baja California, in Mexico, on Saturday, said officials with the Balloon Museum.

The balloon, which relies solely on an enclosed chamber of helium gas for lift, is different from hot air balloons and so-called Roziere balloons, which rely on both hot air and lighter-than-air gas. Roziere balloons have by far the greatest range of the three types.

They had earlier taken a track that would have brought them to southwestern Canada, but because of weather changes, they opted for the path toward Mexico, officials said.

Their records must be officially certified by the National Aeronautic Association and the Federation Aeronautique Internationale, which can take months, a mission spokeswoman said.