UPDATE: Officer Michael Monahan was released from the hospital on Thursday.

LONG BRANCH - Authorities are offering $25,000 in rewards for information in the attack that left a Long Branch police officer unconscious early Tuesday.

Shortly before 2 a.m. on Tuesday, Long Branch police officer Michael Monahan was on patrol when he noticed what he believed to be several subjects with flashlights near an abandoned building near the intersection of Westwood and Bath avenues, Long Branch Public Safety Director Jason Roebuck said in a release.

The subjects fled after Monahan, a 12-year veteran of the police force, exited his vehicle to investigate.

A foot chase ensued and Monahan was able to apprehend one subject, before being struck on the back of his head and knocked unconscious, Roebuck said.

Other officers responding to the scene were unable to reach Monahan on the radio and eventually located him by the light given off by his flashlight on the ground.

Monahan was found face down and unconscious. He was transported to Jersey Shore University Medical Center in Neptune where he remained under observation for a head injury as of Wednesday afternoon, Roebuck said.

"We are hopeful and optimistic for a full recovery," Roebuck added. "This is another example of the sacrifices that police officers endure daily, putting their lives in danger to protect the public. We are proud of Officer Monahan for his dedication to duty and hope he has a speedy recovery."

New Jersey State PBA President Patrick Colligan said in a release the NJ State PBA is offering a $20,000 reward through the NJ COP SHOT program for information leading to the arrest and conviction of anyone responsible for the assault on Monahan.

"Our thoughts and prayers are with this officer, his family, and all the officers within the Long Branch Police Department during this difficult time," Colligan said in a release.

Roebuck said the investigation was still active as of Wednesday afternoon.

Anyone with information about the incident is asked reach out to Detective Joe Spitale of the Long Branch Police Department at 732-222-1000.

Anyone with information can also contact Monmouth County Crime Stoppers by calling 800-671-4400 or texting "MONMOUTH" and the tips to 274637 (CRIMES).

Monmouth County Crime Stoppers will pay up to $5,000 for information that leads to the identification, arrest and prosecution of any suspect(s) in the assault of a police officer.

Rob Spahr may be reached at rspahr@njadvancemedia.com. Follow him on Twitter @TheRobSpahr. Find NJ.com on Facebook.