A climber airlifted with altitude sickness from near the peak of Japan’s Mount Fuji last week was rescued again just four days later after returning to the slope to retrieve his cell phone, authorities announced Monday.

The climber, identified only as a 27-year-old Chinese student living in Japan, made an emergency call on April 22 after developing symptoms of altitude sickness, Shizuoka prefectural police said. His climbing irons were also damaged.

The man was subsequently airlifted from the mountain.

The mountain’s hiking trails are officially open only from July to early September, although there is no penalty for hiking off-season. (Getty Images)

The 12,388-foot-high mountain was designated a UNESCO World Cultural Heritage site in 2013. The mountain used to be a place of pilgrimage and is now increasingly popular among hikers.

Last year, local authorities attempted to control overcrowding and risks from rushed overnight climbing along rocky slopes to view the sunrise by introducing an entry fee and cap on the number of people who can enter the most popular trail. Similar rules will be introduced on other main trails this year.

The Associated Press contributed to this report.