A $22,000 reward is being offered for the arrest and conviction of the person who allegedly shot and injured a police officer in Queens.

Police Commissioner Ray Kelly says the suspect is John Thomas, 24, seen above.

Investigators with the New York City Police Department say Sergeant Craig Bier, 44, a member of the Queens gang unit, and his partner tried to stop Thomas on a bicycle around 10:30 p.m. Wednesday on 107th Avenue and Union Hall Street.

Police say Thomas fled down an alley, then climbed a fence and jumped on the roof of a van.

As Bier tried to block Thomas' escape, the two exchanged gunfire and he was hit with a bullet that entered his left thigh and lodged in his right.

Commissioner Kelly says Bier fired six shots to Thomas' four.

Bier was transported to Jamaica Hospital and is recovering from surgery to remove the bullet.

A wanted poster being displayed says Thomas may also have been wounded.

"A Queens South impact team in the area heard the gunfire and drove in the direction of the shooting. They saw Sergeant Bier on the sidewalk, put him in their vehicle and rushed him here to Jamaica Hospital," Kelly said.

A 9mm gun was recovered by detectives near the scene.

Mayor Michael Bloomberg said the shooting is another reminder that elected officials need to get tougher on guns.

"I don't know how many mass murders or individual murders or shootings we have to have before we have somebody that's got the courage to stand up and say the public deserves protection," said the mayor. "And I'm not going to worry about the politics of this, I'm just going to go out and do what's right. That's what this country needs."

Activists demonstrated near the scene of the shooting Thursday morning and echoed the mayor's calls for stronger gun control.

"The Second Amendment protects those who are legally holding guns. This is about individuals who have illegal handguns in our community, and that's a problem," said Tony Herbert of Advocates Without Borders.

"Our community is shooting each other. I mean, there's got to be stiffer laws with these guns," said Juan Rodriguez, a Cypress Hills activist. "Of course, the buyback program is good, it's a good program. But for some reason or another we still have more guns on the street."

Bier is a 15-year member of the NYPD who has earned 65 medals over his career, including 14 medals for meritorious police work, according to Kelly.

He is the 10th NYPD officer to be shot this year.

Anyone with information on the case should contact the Crime Stoppers hotline at 1-800-577-TIPS, or text CRIMES and then enter TIP577, or visit www.nypdcrimestoppers.com.

Mayor, Police Commissioner Discuss Shooting Of Policeman

NY1 VIDEO: Mayor Michael Bloomberg and Police Commissioner Ray Kelly discussed the shooting of Sergeant Craig Bier early Thursday morning at Jamaica Hospital Medical Center in Queens.