A tube carriage was hit by what is believed to be an air rifle pellet.
At around 5.35pm last night (May 21) passengers on the Central Line service between Buckhurst Hill and Loughton heard a loud bang.
One of the windows of the carriage shattered.
No one in the carriage was injured.
Investigations by British Transport Police and Central Line staff are ongoing.
Police are currently unsure whether the projectile was a stone or a pellet from an air riffle.
Anyone with any information should contact British Transport Police on 0800 40 50 40 or text 61016 citing reference 430 of 21/05/18.
Comments: Our rules
We want our comments to be a lively and valuable part of our community - a place where readers can debate and engage with the most important local issues. The ability to comment on our stories is a privilege, not a right, however, and that privilege may be withdrawn if it is abused or misused.
Please report any comments that break our rules.
Read the rules here