A Russian military plane slammed into a block of flats in Yeysk in a region bordering Ukraine.
Video showed an inferno in Krasnodar region after the warplane loaded with ammunition struck the apartment block.
The pilots ejected seconds before the horror.
A dramatic picture shows the parachute of one of the pilots as he came down against a backdrop of the fireball apartment block.
The Su-34 plane hit the residential building on Kommunisticheskaya Street.
It was not immediately clear how many casualties there were in the carnage of the blitzed apartment block.
Early reports said one person was killed and three including a child were hospitalised in a grave condition.
Yeysk is a resort and port on the shore of the Taganrog Gulf of the Sea of Azov in Krasnodar region, which borders Ukraine.
A statement from the Russian defence ministry admitted: “Today, while taking off on a training flight from a military airfield of the Southern Military District, an Su-34 aircraft crashed.
“The plane crashed within the city of Yeysk.
“According to the report of the ejected pilots, the cause of the crash was the ignition of one of the engines during takeoff.
“At the site of the crash of the Su-34 in the courtyard of one of the residential areas, the fuel of the aircraft ignited.”
War Telegram channel Kotsnews said: “It was an Su-34 of the 277th Bombing Aviation Regiment.
“So far, the main version is that it was birds getting into the engines at takeoff.
“The pilots ejected.”
There were “possible casualties among local residents”.
The crash came as people were eating their evening dinner.
He said there were “no rockets on the plane, but there were shells for the cannon".
“Their detonation can be heard on videos,” he added.
The first to fifth floors of the nine-storey block of flats were engulfed in fire, eyewitnesses said.
A daughter called her mother saying: “It fell right over our heads, everything is covered with black smoke.
“Mum do you realise that 10 more metres and it could have been us?”
Fire teams were working at the scene.
“Extinguishing the fire is difficult because of the large flames and smoke,” said one report.
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Regional governor Veniamin Kondratyev, 52, was at the scene.
