The nightclub in which a London student was crushed to death had continued to sell tickets even after the event was sold out, the victim’s friend has claimed.

Nabila Nanfuka, 22, is reported to have suffered a heart attack as revellers stampeded to catch their coaches home at the end of the club night in Northampton.

According to reports, there was an announcement at about 3.30am that told clubbers they had 10 minutes to catch their coaches. Students had travelled to the event from 17 different universities.

It is said that a fire alarm went off as the crowd surged towards the exit, perhaps causing further panic and adding to the crush.

Nanfuka’s close friend, Birungi Nakiwala, claimed: “We found out it was a sold-out event and then we were told on the day you can get tickets at the door. I didn’t understand how they were still letting people in.”

Another clubber told reporters: “People were pushing, pushing, pushing to get out. I ended up on my front, trying to find a gap to breathe through, but there were so many people on top of me. I’m sure I passed out for a few minutes.”

Police said that they are investigating whether the club had exceeded its capacity. Council chiefs have shut the club as the investigation gets underway.

Nanfuka was apparently trampled to death when she was knocked down while descending steep steps. She suffered a cardiac arrest and, after being rushed to hospital, was pronounced dead.