LONDON, May 3 (Xinhua) -- Nearly 30 people have been injured in an explosion during a celebration in north London late Wednesday.

The explosion was reportedly sparked by mobile phones being thrown into bonfires, which are a tradition for Lag BaOmer, an annual Jewish festive event.

Hundreds gathered in Stamford Hill at the time. Around 10 people are believed to have been injured by the fire, while 20 others injured in the scramble to escape, local media reported.