“Metropolitano de Lisboa has already opened an investigation to investigate the circumstances in which this situation occurred and will release new information through its communication channels”, said the company in a statement.

In a statement, ML states that train circulation on the Yellow and Green lines has been interrupted since 7:48am and that there were no personal injuries.

“At the moment it is not possible to predict the duration of this interruption, and Metropolitano de Lisboa is evaluating the possibility of starting train circulation on these two lines in sections”.

A small derailment of a train on the ML Green Line at Alvalade station this morning did not cause any injuries, but two people had to be assisted, according to the PSP and firefighters.