Complicating the security landscape further, there are two or three armed extremist groups that oppose the government, as the protesters do. But these groups seem bent on disrupting the peaceful protests with armed attacks.

Their presence makes it possible for rogue elements within the various government security forces to operate with impunity and blame extremist groups for their activities.

President Salih said the shooting of the protesters was “a criminal, armed attack carried out by criminal and outlaw gangs.” He admonished the security forces, saying their responsibility was not only to protect “the peaceful demonstrators and public and private property” but also to “chase the outlaw criminals and arrest them and bring them to the judiciary for punishment.”

The protesters were shot near the Sinak Bridge, which spans the Tigris River — one of three bridges that have been taken over by protesters. In addition to the deaths, about 100 people were wounded in the shootings.

The assault started in a six-story parking garage that overlooks the bridge and the Tigris River. The garage is one of two buildings that have become protester strongholds.

“What happened was that at 8 p.m. yesterday, we were surprised when we heard a fight happen on the fourth floor and then suddenly there was shooting,” said Murtada Saad, 18, a tuk tuk driver who works around the bridge and had driven his three-wheeled vehicle into the building.

Soon after, there was shooting outside, as well as in a nearby square which the protesters have also occupied. Witnesses described a chaotic situation in which they said some gunmen appeared to be wearing the military uniforms of government forces. Some were wearing uniforms of the Popular Mobilization Forces and some were in civilian clothes.