British Transport Police say it happened overnight Monday (2nd July) into Tuesday (3rd July)
Images of 4 large tags spreading the length of at least 3 windows have now been released.
BTP Devon & Cornwall tweeted to say those responsible risked their lives trespassing on the railway and their actions could land them with an unlimited fine or up to 10 years in prison.
They're now looking for those who caused the damage.
Plymouth fly-tipper brought to justice
Council wins long court battle
Torbay waves goodbye to Blue Flag beaches
Council ditching national accolade
Woman died after oxygen supply turned off
Warning further deaths could happen without action
Massive data centre could be built near Devon
Bigger than 180 football pitches
Two further arrests after body found at Plymouth marina
Two males aged 17 and 18 bailed
