According to the Sun, the troops fired on the protesters in the city of Benghazi on Friday as they rallied outside a military compound used by ruler Muammar al-Gaddafi.
"People were shot in the legs, chest and head," one witness said.
A source at a Benghazi hospital confirmed it saying that the most common injuries were bullet wounds to the head, chest and neck.
Meanwhile, Amnesty International said that security forces had killed at least 46 people during the past three days.
"The alarming rise in the death toll, and the reported nature of victims' injuries, strongly suggests that security forces are permitted to use lethal force against unarmed protesters calling for political change," said Malcolm Smart, the Amnesty's director for the Middle East and North Africa.
Colonel Gaddafi is the Arab world's longest-serving leader, having ruled oil-rich Libya since a coup in 1969. (ANI)