British Transport Police has released video of a man forcing his way through closed barriers at Brimsdown level crossing in Enfield, North London, at 6am on Tuesday 5 May.
He narrowly escapes being hit by a speeding train.
Inspector Stephen Webster of BTP said: “This was a completely needless incident, and one that requires our attention and an investigation at a time when officers could be supporting the latest guidance around Covid-19, and helping to keep the travelling public safe.
“The warning signs, barriers and flashing lights are all there for a reason. Some trains travel at high speed, and one that you think is in the distance could be bearing down on you in seconds.
“This incident could have very easily gone the other way, as it has in the past, and this man may not have returned home to his loved ones.
“Don’t ignore the small wait it takes for a train to pass, don’t risk your life.”