A window has smashed, apparently spontaneously, showering the pavement below the rear of 33 Canada Square in Canary Wharf with shards of glass.
An area covered in debris near the Jubilee line station exit and Protein Haus stand in Reuters Plaza to the rear of the Citigroup Centre has been cordoned off.
Victoria Rudzeviciute, who works at Protein Haus said a part of the glass pane fell to the ground at around 3pm before more followed at around 4pm.
She said: “I just saw something fall by the side and heard the noise of glass.
“No-one was underneath it to get hurt. They put a cordon up straight away.”
Some have speculated high temperatures may have contributed to the glass breaking.
A spokesman for Canary Wharf Group said the cause of the breakage was not yet known and it was too early to comment on whether it could have been caused by the strength of the sun.
He said: “A pane of glass has fallen and smashed on the floor.
“We don’t know the reason why. We are trying to find that out, and we are trying to clear the ground and re-open the area. No-one has been hurt.”
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