Marco_Piunti/iStock(CHICAGO) -- A 25-year-old Chicago police officer is "battling for his life" after he was shot in the head while off-duty, according to the superintendent.

The officer was driving with a woman at about 1:38 a.m. Wednesday when he noticed a black Toyota following him and they called 911, Chicago Police Department Superintendent Eddie Johnson said.

Someone in the Toyota fired shots at the officer's car, hitting him in the head, Johnson said.

The woman in the car was not hurt and is cooperating with police, he said.

No one is in custody but video camera footage captured part of the incident and is being reviewed, Johnson said at a news conference on Wednesday.

The unnamed officer, who has been on the force for two years, underwent surgery and was in critical condition on Wednesday, Johnson said.

The officer is "showing signs of improvement," Fraternal Order of Police President Kevin Graham said at the news conference.

"He actually gave a thumbs up," Johnson said.

The injured officer serves the same district where his father -- who retired last year -- worked.

Johnson said he worked alongside the injured officer's father, and now that injured officer works with Johnson's son, another Chicago cop.

As the officer's "clinging to life," Johnson stressed the need to stop gun violence in the city.

"My heart goes out to this young man's family and his friends," he said. "I also want to offer a prayer to all those who have suffered as a result of gun violence in Chicago. These senseless shootings just have to stop. And I'd like to renew my call for common sense gun laws."

"You ask yourself why does this keep occurring. And the simple fact is we just have too many guns in Chicago and too many people willing to use them," Johnson said. "And I don't blame any particular group of people except the ones puling the triggers. ... It just seems to me that if we focused as a society on the people that pull the triggers that maybe we could reduce this a lot quicker. But we choose to point the blame at everybody else."

"We need to put the guns down in the city of Chicago," he said.

Anyone with information is asked to call the police department at 312-747-8380.

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