Atlanta police found the bodies of two homeless men killed in their sleep just miles from

Someone is targeting Atlanta's homeless community and killing them while they sleep, police say.

Atlanta's homeless community is being urged to stay alert and take extra precautions after authorities say two homeless men were fatally shot while they slept in two separate -- but similar -- incidents, NBC News reports.

On Monday, a man in his forties was found dead in downtown Atlanta in a park where he was known for sleeping at, WXIA reports.

Homeless: Two homeless men, Tommy Mims, 64, (left) and an unnamed man (right)believed to be in his forties were found dead in similar killings as they slept on the street

Bridge: Mims was found dead on a sidewalk under a railroad bridge (above) on Northside Drive in atlanta

'It appears that the victim had been sleeping,' Capt. Paul Guerrucci, Atlanta police homicide unit commander, said in a news conference, 'and that someone shot him multiple times while he slept.'

Just two days later, the body of 64-year-old Tommy Mims was found under a bridge.

Found about two miles apart, both men suffered gunshot wounds and appeared to have been killed while they slept.

Guerrucci said that it is believed that both men were shot in the evening.

'Please be aware that it appears that we have somebody that is targeting people that are sleeping at night, and we're very concerned about that,' Guerrucci said.

Police are struggling to find a motive behind the two killings, which occurred in the same week, and say they don't believe the killings were a result of a dispute or a robbery.

Captain: Capt. Paul Guerrucci said the killer is believed to be targeting the homeless as they sleep

Motive: Police have not found a motive for the killings and are urging Atlanta's homeless community to take extra precautions and use a 'buddy system' on the streets

Anita Beaty, of the Metropolitan Atlanta Task Force for the Homeless, told NBC that the word is being spread through homeless shelters and on the streets that the homeless should be vigilant and use a 'buddy system.'

'It's bad enough that you're sleeping outside in the cold, but to be murdered?,' Beaty said.