A 44-year-old man has been seriously injured after being shot in the Shenfield railway station car park this morning.
UPDATE: The British Transport Police have confirmed they are looking "for a man with a balaclava".
A tweet from the force read: "Were you at Shenfield station car park shortly before 6am on Friday morning?
"Did you see a man in a balaclava in the area?"
Call 0800 40 50 40, quote 48 of 24/1
East of England Ambulance Service have now confirmed they were called to a shooting at 5.50am.
A spokeswoman said: "A man has been taken to hospital after shooting incident in Shenfield.
"The East of England Ambulance Service NHS Trust (EEAST) received a call at 5.50am and sent an ambulance, a duty manager, and the hazardous area response team (HART) to the scene.
"The casualty, who is believed to be in his 40s, sustained injuries to his leg.
"He was taken to Basildon Hospital by ambulance.
"Upon arrival his injuries were not thought to be life-threatening."
A spokeswoman from British Transport Police said: "Officers from BTP and Essex Police attended Shenfield railway station this morning after reports of a man with leg injuries in the car park at the station.
"The incident was reported to BTP at 5.51am.
"On arrival officers located a man in his 40s with injuries to his leg.
"The man was taken by ambulance to Basildon Hospital. His injuries are not believed to be life-threatening.
"Enquiries are ongoing to establish the full circumstances including how the man came to be injured.
"Anyone with information should call BTP on 0800 40 50 40 quoting reference 48 on 24/1."
Rail operator Greater Anglia sent out the following tweet at 6.40am this morning: “The station has been closed by emergency services.
"Trains are running but won't be stopping at Shenfield until further.”
The car park, off Mount Avenue remains cordoned off by police officers.
C2Care accepting tickets on "reasonable services" between West Horndon to Fenchurch Street following the incident.
Reports of delays appeared on Twitter as early as 5.30am today.
Rumours of the shooting circulated on the social media website.
Tom Vale @tomandyvale said: "no trains? someone been shot in shenfield station car park? wtf...."
Richard Boast @RichardBoast said: "Just heard someone just got shot at SHENFIELD station in the car park, no trains at the mo. Investigating."
Cllr Graeme Clark @ShenfieldGraeme said: "Commuter alert! Just been told no trains stopping at Shenfield until further notice. Now on Metro train to Liverpool St. Don't know reason."
Sophie Gilbert @sophiegilbs said: "Shenfield station all taped off by police... Eeeeek what on earthhhh."
Charlie briley @charliebriley said: "Anyone going shenfield , have to go Brentwood ! Been an incident loads of old bill !!!"
Nwankwo Kanu @Nwankwokanu1981 said: "Got on train at #shenfield driver asks if police is on board. Then some bird jumps up and says she heard gun shots."
Did you see what happened? Do you know the man who was injured? Call the newsdesk on 01245 602733.