The push and capture of the giant cave complex that once housed al-Qaida's chief would be a major scoop for the Islamic State group in its rivalry with the Afghan Taliban.
Attahullah Khogyani, a spokesman in Nangarhar, says IS attacks began late last night. He says clashes continued into the day with IS militants battling the Taliban and some local villagers.
Khogyani says IS militants by today had managed to occupy some areas around Tora Bora, but not the bin Laden hideout itself. He says there are unspecified casualties on both sides.