Heavy fighting in Sudan's west and south has killed at least 27 people and left dozens wounded, residents said Tuesday, with the country's envoy to the United Nations saying he was "deeply concerned."

In separate incidents, clashes broke out in the restive Darfur region regarding a bitter land dispute, leaving 16 dead, while in the state of South Kordofan, 11 people were killed after an argument between two people reportedly escalated into clashes with firearms.