Atlanta police said Wednesday the fourth early-morning carjacking in three days and two armed robberies in the Midtown area could all be related.

All of the crimes have occurred in the morning between 5 and 7 a.m. in the Midtown and south Buckhead area within a relatively tight radius, and the latest two crimes happened Wednesday, according to Carlos Campos, Atlanta police spokesman. Three Infinitis, a Toyota 4Runner and an Audi have all been stolen during the carjackings, police said.

“We’re very concerned because these individuals are armed,” Deputy Chief Jeff Glazier said during an afternoon press conference. “And during one of the incidents, they fired their weapon at the victim.”

The string of crimes began Monday at approximately 5:30 a.m, when police were called to Montgomery Ferry Road in northeast Atlanta. A man told police as he was returning to his vehicle, a man dressed in all black came out of the bushes with a handgun. The suspect pointed the gun at the victim and demanded his keys, according to police.

As the victim dropped the keys, another man dressed in black appeared and both suspects drove away in the victim’s silver 2013 Toyota 4Runner, police said.

Wednesday around 6:30 a.m., officers were called to Melante Drive for another carjacking. The victim noticed a silver Infiniti G35 traveling behind his vehicle near the 2000 block of Cheshire Bridge Road, according to police. After pulling into his driveway and getting out of his car, two men exited from the rear of the Infiniti and walked toward him.

Two suspects pointed guns at the man and ordered him to the ground, taking his keys and phone and leaving in the man’s 2015 black Audi A8. The second suspect followed in the Infiniti. The victim told police he believes there were four suspects.