Transcript for Cops arrest man wanted for gunning down police officer
murdering a Taliban bombmaker. An arrest in the case of a Mississippi police officer ambushed and killed right outside police headquarters in biloxi. Steve osunsami has the latest and, Steve, this officer just months from retirement. Reporter: That's right, George. A biloxi police officer was driving home from work last night when he spotted the accused gunman walking the streets. That's how it happened. Police are calling it a cold-blooded killing and they are glad that the suspect is in custody. When they brought him in overnight people waiting outside the police station cheered and on the sidewalk a solemn line of heartbroken police officers stood in procession. 19-year-old Darian Atkinson had a grin on his face and mumbled words and he is the man seen walking into the same biloxi police station shortly before gunning Dow officer Robert Mckeithen in the parking lot outside. It's been a long couple of days. We want this guy to pay for what he's done. Reporter: Mckeithen died at the hospital just down the street from the police station and leaves behind a wife and four children. The air force veteran who friends say enjoyed working the night shift was set to retire this year. He's described as a gentle man with 24 years on the force and awarded a medal after valor for saving the lives of four children during hurricane Katrina. They don't know if he was targeted or the attack was random but their focus on the family of the officer who was killed. I hope in some small way making this arrest will bring them some closure. Reporter: The accused gunman did not have a criminal record that police know of. A memorial for the officer killed is scheduled tonight, robin. There in biloxi, thanks so much, Steve.
This transcript has been automatically generated and may not be 100% accurate.