At least 12 people were injured, two seriously, and more than 90 families were displaced, officials said.
Lt. Lavender said it was unclear how many residents were missing from the fire because a number of families were away on spring break.
Shocked residents still wearing nightclothes were returning to survey the destruction and anxious relatives and friends were searching for loved ones at the apartments on Hudnall Street at Cedar Springs Road.
Apartment resident Philbrick Keith Grady, 49, was at work when the fire started but rushed home to help roommate Marion Roberts, who is asthmatic. Mr. Roberts, 41, a health care worker, was at home and called his sister Ann Smith of Red Oak for help.
Ms. Smith said her brother called about 11:40 p.m. "Ann, I need you," he told her. "There's a fire here." She managed to get a 911 operator on a three-way call with her brother, who was in a third-story unit.
"Ann, I can't breathe," he kept saying. "Should I jump?"
She left him on the line with the operator and raced to the complex. Mr. Grady also rushed to the apartment to find the complex in flames.
Mr. Grady and Ms. Smith searched for Mr. Roberts at local hospitals and the American Red Cross shelter set up at Grauwyler Recreation Center on Harry Hines Boulevard.
"We went everywhere and he has not contacted us," Mr. Grady said. "He's still in there."
"I don't think he got out," Ms. Smith said. "I could hear him gasping for air."
Lt. Lavender said firefighters were trying to determine why the fire became so advanced before someone called 911. The first firefighters reached the buildings in three minutes after getting the call at 11:30 p.m., with a total of 175 firefighters ultimately responding to the scene.
"Our first arriving firefighters said the whole building was on fire. That put us behind the eight ball fighting the fire," he said.
Brandy Calderon, 23, who lives at the complex with her 26-year-old husband, Leo, said she called 911.
"While we were waiting you could hear people screaming," Ms. Calderon said. "Some people tried to get ladders to help out. No one could get in the hallways. The whole thing was on fire."
Added Mr. Calderon: "There were no lights. No alarm went off. We just heard people screaming."
Tiffany Taylor, 21, lives at the complex, as does her sister, Nastassia Collier, 23, who resides in a separate unit with her 1-year-old daughter. Neither could see whether their apartments still existed, but Ms. Collier said she assumed hers was gone.
Ms. Taylor said she awoke around midnight when she heard the fire trucks. She looked out the patio window and saw flames.
"We have smoke alarms but didn't hear anything. We just saw fire," she said.
With firefighters yelling at her to stay back, Ms. Taylor ran to Ms. Collier's unit and beat on the door.
"I looked out my patio door and saw nothing but flames. My sister was screaming, 'Get out! Get out!' My door was scorching hot," Ms. Collier said.
Ms. Collier recalled a scene of chaos and agony.
"This is really a tragedy. This fire was so bad," she said. "I don't think all these people made it out. Everyone was screaming and looking for their loved ones."
Raul Rivera said he had failed to find his 60-year-old aunt at the Grauwyler shelter. So he came to the Love Field-area apartment complex, where sky now replaces what once was her third-floor unit.
"She was here yesterday," Mr. Rivera said. She's the kind of person, if you knock on her door, she won't open it. ... She's in good health, but you know if you panic, it can be bad."
Dallas-Fire Rescue said at least 40 units were damaged. Black pieces of wood, charred like toothpicks, littered the grounds. Chunks of burned debris were scattered across the parking lot, and at least a dozen cars sustained damage like shattered windows, body damage or scorching.
Firefighters said a number of people jumped from balconies to escape the flames.
"I went to the door and I couldn't even get out," Priscilla Johnson said. "I had to jump down from the third floor, slide down on the wood to get out. I saw my whole apartment go up in flames."
Shaun Weldon, 27, was hanging out Sunday night with four friends. "I heard someone slamming on my next-door neighbor's door. She was yelling in Spanish and my friend translated, 'The apartment is on fire,'" Mr. Weldon recalled.
The group helped Mr. Weldon grab some of his belongings, including computer equipment, the big-screen TV and a suitcase full of clothes. He said he knows of at least two neighbors who jumped from third-story balconies, one of whom broke his arm.
The complex contains approximately 300 apartment units. Public records show the complex was built in 1975.
"It's really emotional; you can imagine," Red Cross spokeswoman Anita Foster said. "That's 93 families who, in one fell swoop, have lost everything they have."
She said displaced families will need immediate help with housing, food, and clothing. Many will require mental health assistance to deal with the magnitude of the tragedy.
"It's going to be a big job for the Red Cross and for the community to come together to help," Ms. Foster said.
Written by The Dallas Morning News