The man, who was attacked while out on a run at Naroncolo, near the town of Dro, is not in a life-threatening condition, the sources said.
Forest rangers are investigating to try to identify the animal.
A 26-year-old trail runner was killed by a bear he accidentally ran into in Trentino last year.
The bear identified as being behind that fatal attack, JJ4, was captured and the authorities ordered it be put down, but legal action by animal rights groups prevented this.
JJ4 is set to be transferred to a reserve outside Italy.
Tuesday’s attack comes less than a week after a Swiss woman and her three children had a close encounter with a bear and at least one cub near Lake Molveno.
In March, the provincial authorities approved a decree authorising the culling of up to eight ‘problematic’ bears a year in 2024 and 2025.
This decision came after the animals’ numbers grew significantly following their reintroduction to the area between 1996 and 2004, but animal rights groups have since launched challenges.
ANSA
