Saudi Arabia says an overnight fire at a hospital in the southwestern province of Jizan has killed at least 31 people and injured over 100.

Saudi Civil Defense spokesman Maj. Yahya bin Abdullah al-Qahtani says the cause of the blaze remains unknown. It broke out in the early hours of Thursday around the hospital's intensive care, maternity and neonatal care wards.

There was no immediate breakdown of the victims available.

The kingdom has suffered a number of large-scale accidents this year, namely a crane collapse that killed 111 and a stampede that killed at least 2,400 during the hajj pilgrimage in September, according to an Associated Press count.