Scott Olsen survived two tours of Iraq, but his life could be over after being critically injured by a police projectile at Occupy Oakland, The Guardian reports. He's 24 years old.

As we know, Occupy Oakland got incredibly ugly this week as police tried to remove protesters from their camp in front of City Hall by using tear gas, fire crackers, and rubber bullets.

Olsen suffered a head injury on Tuesday night, and is now in critical condition in Oakland's Highland Hospital. Jay Finneburgh, a photographer on the scene, managed to witness and take pictures of the incident. Police policy specifically prohibits the firing of these weapons at a person's head.

"This poor guy was right behind me when he was hit in the head with a police projectile. He went down hard and did not get up," Finneburgh wrote.

At first, Doctors told Olsen's friends that he was in critical, but stable condition. Now they're being told that his skull has been fractured and his brain is beginning to swell. Neurologists are in the process of determining whether or not he will require surgery.

According to Keith Shannon, a friend who served with Olsen during his time in Iraq, Olsen was hit in the head with a tear gas or smoke canister, and he has the scar on his head to prove it.

Meanwhile, Oakland police admit that they used tear gas and baton rounds, but have denied the use of flash bang grenades. Protesters, however, say they saw police use them, and the more video that comes out, the harder it is to believe the police.

Olsen hails from Wisconsin, served tours of Iraq in 2006 and 2007, and is active in both Veterans for Peace and Iraq Veterans Against the War.

You can see a video of him collapsing and injured below.