Protesters dressed in red suffragette's sashes threw bricks through glass doors at the Department for Transport (DfT).

At 4.50am today bricks reported to have been covered in notes reading “No third runway, the Suffra-jets are back” were thrown through the glass doors of the DfT’s Westminster building and police are now investigating.

However direct action group Climate Rush, which staged the suffragette themed picnic protest at Heathrow’s Terminal 1 on Monday, January 12, denied responsibility.

A spokesman said: “Climate Rush was not involved in the incident that occurred at the Department for Transport in the early hours of this morning.

"However, we are not surprised that this has happened. The Government has made the wrong decision in deciding to build the third runway at Heathrow and emotions are running high.

“Climate Rush is a diverse and fluid group of women and men that includes school teachers, politicians, labourers, editors, photographers, administrators, students, parents and campaigners to name but a few but we are all united by our fear of the threat posed by imminent climate change.”

A spokesman for the DfT said "We can confirm a window was broken at the Department's Great Minster House corner reception at about 4.50am today.

"Police are investigating. No further comment can be made."