A packed student party ended in terror when a floor collapsed beneath the weight of 100 revellers – sending them plummeting into a basement.
Men were said to have clambered over women to escape as the wooden floor plunged 8ft.
Paramedics said it was a “miracle” that no-one was seriously hurt.
Birmingham City University student Qadar Adde, who was DJing when the drama began at 1.20am on Saturday, said: “We were all dancing and then we felt the floor wobbling.
“All of a sudden, we heard a loud bang and we crashed through the floor.
“People started to panic and boys were climbing over girls to get out.
“It was scary, especially when the fire service told us it could have happened from the first floor.
“We were all really lucky. A huge piece of concrete fell off the wall and that could have seriously hurt someone.
“Luckily we got away with cuts and bruises. The most important thing is no-one was hurt.”
Around 100 guests – all from BCU – were at the party at the house in Livingstone Road, Handsworth, Birmingham, according to the Birmingham Mail .
Qadar, a 21-year-old business studies student, said the revellers were celebrating three different birthdays.
He said fire crews believed a damp problem was behind the collapse.
The floor fell so far that a fireplace in the basement could be clearly seen from the lounge above.
Another witness told the Birmingham Mail: “The music was in the living room where most people gathered and danced. “Some said they felt something wrong with the floor.
“It eventually collapsed due to the weight of so many people.
“The authorities came to solve the situation and cleared people out of the area.” The six second year students living in the house were only allowed to return after electricians and structural surveyors had checked it was safe.
But Qadar, who lost all his DJ equipment in the terrifying incident, said he was worried his ground floor room could collapse as the floor was wobbling.
The boys were last night (SAT) waiting for their landlord to contact insurers.
A West Midlands Ambulance Service spokesman said: “On arrival at the scene, approximately 100 people had managed to get themselves out of the house after part of the floor had collapsed into a vacant basement area.
“It is amazing that none of them had suffered any injuries in what had the potential to be a very different situation.”
Three ambulances, two paramedic area support officers and a hazardous area response team were sent to the scene, along with police cars and fire crews.
West Midlands Police were unavailable for comment, despite repeated calls.