Mass panic was sparked at Westfield in Stratford after the shopping centre was evacuated in a fire alert.
The Met Police said a fire alarm had been sounded and officers were at the scene.
We believe it’s a small fire at this early stage, a spokesperson tweeted.
The force later confirmed there had been a fire and police cordons at the shopping centre were lifted.
Unsubstantiated fears of a possible terror attack spread quickly among the crowd as the UK remains on high alert following previous attacks earlier in the year.
TV director Erron Gordon tweeted: At Westfield Stratford and being evacuated. People running shouting something about an attack. Everyone looking very worried. No more details ATM.
Westfield Stratford City evacuated as shoppers are seen running and screaming, Janez Feasey wrote. Emergency services on scene.
Another Twitter user said: Just witnessed the maddest Lion King stampede at Stratford Westfield because of a bomb scare. I ran too fam.