Transport for London has said bus routes 281 and H20 are on diversion in both directions due to a "police investigation" in Whitton Road.
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Police enquiries continue into the ‘powdered substance’ incident on a bus in Hounslow. We will keep readers informed of any developments on our website.
Thank you for joining us on our live blog today.
What we know so far
This is our latest story on the incident in Hounslow this morning.
Here’s all the information we know so far:
Buses return to normal route
Both buses- 281 and H20 - have now returned to their normal routes after they were placed on diversion following the police investigation on Whitton Road.
Whitton Road in both directions has re-opened between Pownall Road and Cross Lances Road / Heath Road following earlier police investigation.
Fire Brigade statement
Firefighters attended the “chemical incident” in Hounslow this morning.
A spokeswoman for the London Fire Brigade said:
We were called at 10.59am to reports of a chemical incident on Whitton Road in Hounslow.
One man was treated at the scene by the London Ambulance Service but was not taken to hospital.
The Fire Brigade said they are no longer at the scene.
Police have confirmed no arrests have been made at this stage of the investigation.
Enquiries continue into the incident.
Witnesses urged to call police
Passengers on the bus and any witnesses to the incident on Whitton Road, Hounslow are urged to contact Hounslow CID.
Police can be contacted on 101 or via Twitter @MetCC.
Anyone who wants to remain anonymous can contact Crimestoppers on 0800 555 111
Footage taken by @Kabulii shows police have sealed off part of Whitton Road and bus 281 remains inside the taped off area.
A bus has been evacuated after a powdered substance was thrown at the driver.
A statement from the Metropolitan Police said:
At this early stage, it is believed a fire extinguisher was discharged by two people on a moped.
The driver is being treated at the scene. His injuries are not life-threatening or life-changing.
The bus has been evacuated as a precaution.
Officers from the Met Police, paramedics from the London Ambulance Service and firefighters from the London Fire Brigade are in attendance.
Metropolitan Police confirm 'powdered substance thrown at bus'
The Metropolitan Police said it was called at 11.01am on Friday (August 11) to reports of a powdered substance being thrown at a bus on Whitton Road, near the junction with Pownall Road in Hounslow.
Picture of police at scene
This picture taken from footage at the scene shows police tape and officers near a bus on the road
Buses on diversion
At least two bus routes have been places on diversion following an incident on Whitton Road.
Routes 281 and H20 are being diverted in both directions while emergency services deal with an incident.
A police investigation is underway at Whitton Road, Hounslow.
The road is closed at the junction of Pownall Road due to an emergency services incident.