[Updated at 11:49 a.m. ET, 6:49 p.m. local time] Forces loyal to Moammar Gadhafi attacked peaceful protesters in Zawiya with mortars and machine guns on Friday, in what a witness called an "indescribable" and deadly assault.

[Updated at 11:20 a.m. ET, 6:20 p.m. local time] Before reports of the killings emerged, a report on Libyan state TV said people in Zawiya, west of Tripoli, and "their public leadership have secured and took control over the city from the armed terrorist elements."

Zawiya was the site of at least 17 killings in one day last month when government forces attacked the city, doctors told CNN.

[Posted at 11:06 a.m. ET, 6:06 p.m. local time] At least 15 people have been killed and 200 more wounded in the Libyan city of Zawiya, an eyewitness told CNN.

Wounded people started arriving at the hospital Friday morning. Most of the injuries resulted from gunshots, and many of the injuries were to the head and chest.

The eyewitness said the hospital is running out of medical supplies.

"There is a river of blood here in the hospital. The situation is very bad," he said.