A 23-year-old Jersey City police officer was shot and killed in what appeared to be a targeted attack outside a Walgreens early Sunday morning, according to Jersey City Mayor Steven Fulop. Police were initially called to an armed robbery but the man who killed Officer Melvin Santiago didn't try to rob the store and instead bragged he was about to be famous moments before the shooting.

Santiago, who joined the force last July and was sworn in December, was fatally shot in the head inside his marked police car as he pulled up to the store just after 4 a.m., Fulop said. His was the first car to arrive, Fulop said.

"It is a tragic situation when any officer is killed in the line of duty," Fulop said in an email. "Melvin was an officer who represented everything one would want to see in a police officer. I know the entire city's thoughts and prayers are with the Santiago family during this difficult time and we mourn together."

The shooter, Lawrence Campbell, 27, allegedly walked in to the drugstore minutes before and asked the security guard for directions to the greeting cards, Fulop said. Campbell, who had a knife, then allegedly left the store but circled back. He was also killed at the scene.

He attacked the security guard, taking his gun, and waited about 4 minutes for police to arrive, Fulop said. Campbell then walked outside and spoke to a witness, apologizing for his actions in the store and telling that person to watch the news, he's going to be famous.

When Santiago arrived, with his partner, Campbell allegedly walked up to the car and fired into it at close range, Fulop said. He then fired three more times at a second marked police vehicle that had arrived, striking that windshield.

Officers in both vehicles returned fire, killing Campbell.

Police later identified Campbell as one of three suspects wanted in connection with another Jersey City homicide, Fulop said. Police are now searching for Daniel Wilson, who has been identified as a person of interest in that homicide.