Police have arrested a man accused of opening fire inside the waiting room of an Atlanta medical practice on Wednesday, killing one woman and wounding four others.

Authorities were in the city’s midtown neighbourhood shortly after noon in search of the suspect, who fled after the shooting.

Police said in a statement on Wednesday evening that the gunman, who they identified as 24-year-old Deion Patterson, was captured in Cobb County, just northwest of Atlanta.

Authorities said Patterson shot five women on the 11th floor of a Northside Medical building, which is in a commercial area filled with office towers and high-rise apartments.

News of the shooting prompted workers and civilians to shelter in place for hours.

Patterson had an appointment at the medical practice and shortly after arriving shot the first victim, law enforcement officials said.

The shooting lasted approximately two minutes before Patterson left the building and went to a Shell gas station and took a pickup truck that had been left running and unattended, authorities said.

Atlanta Police chief Darin Schierbaum said a 39-year-old woman was pronounced dead at the scene of the shooting.

The Fulton County medical examiner’s office identified her as Amy St Pierre.

The four wounded victims were also women, aged 25, 39, 56 and 71.

Atlanta Police deputy chief Charles Hampton Jr said they remained in a critical but stable condition on Wednesday night.

Mr Hampton declined to discuss any details of the investigation or possible motive, saying: “Why he did what he did, all of that is still under investigation.”

Patterson’s mother, Minyone Patterson, who police said had accompanied her son to the medical office, said her son, a former Coast Guardsman, had “some mental instability going on” from medication he received from the Veterans Affairs health system that he began taking on Friday.

She said her son had wanted Ativan to deal with anxiety and depression but that the Veterans Affairs would not give it to him because they said it would be “too addicting”.

She is a nurse and said she told them he would only have taken the proper dosage “because he listened to me in every way”.

“Those families, those families,” she said. “They’re hurting because they wouldn’t give my son his damn Ativan.

“Those families lost their loved ones because he had a mental break because they wouldn’t listen to me.”

She ended the call without saying what medication her son had been taking.

“We are horrified and saddened to hear of the active shooter situation in Atlanta today,” Veterans Affairs press secretary Terrence Hayes said in an emailed statement.

“Due to patient privacy, we cannot discuss the Veteran’s personal information without written consent.”

In a statement, the US Coast Guard said Patterson had joined the service in 2018 and was discharged from active duty in January.

Atlanta mayor Andre Dickens was happy Patterson was arrested and taken into custody alive so he can be prosecuted.

“Right now, we’ve had a successful end to a traumatic day,” Mr Dickens said, while also advocating for tougher gun laws and stressing the importance of police training.

“I hope the city, the region, rests easy that he is in custody, but I also hope that we will stay vigilant to continue to look at a future where individuals who shouldn’t have a gun in possession won’t have one, and also that individuals are brought to justice, and also that we deal with these things that are mental health or easy access to guns.”