She remained there 24 hours later and had been joined by a number of other campaigners.
Pictures from the area on Monday showed workmen standing at the site while the digger remained halted.
Police also turned up at the scene of the protest.
We'll be bringing you the latest updates, pictures and videos from the second day of the protest.
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So what's happened so far?
Anti-HS2 campaigner, Sarah Green, halted the start of work on HS2 for more than 24 hours.
She stationed herself under a digger at Harvil road from 10 am on Monday (October 2) to 5.30pm on Tuesday (October 3) when she and other protesters were evicted by force.
She was protesting in a bid to stop trees being cut down as part of the HS2 high speed rail link project.
By 10:30 am on Tuesday (October 3) morning, she had been joined by four more under the digger and a group of protesters had gathered on the road outside.
The campaign to stall the start of HS2 lasted up until 5:30pm today (October 3) when protesters were finally removed by bailiffs.
The eviction happened shortly after two women were arrested for allegedly assaulting security at the site at around 4:30pm.
Speaking to Get West London from the aftermath of the eviction protester, Daniel Gordonyi, said: “I think we’ve won this battle, it wasn’t the first and it won’t be the last, we’ve shown that we can halt HS2 and that the authorities underestimated our strength.”
Daniel watched on as the five protesters were removed from under the digger. He said: “The bailiffs arrived and put up fences directly around the digger.
“They put up lots of black cloth so we couldn’t see through at all. Then they dragged Sarah and the others out and moved all of us on.”
The eviction took place after several previous attempts by bailiffs to remove protesters that day.
HS2 protesters have now all been evicted from the Harvil road site.
Mark Keir, co-ordinator for Hillingdon Green Party describes the latest from the scene, he said:
“I went off site to sort some things quickly and when I returned I’d missed all the fireworks.
“Everyone has been evicted from the site.
“There’s nobody left there.”
More updates on the way.
TWO ARRESTS MADE: police confirm
Police confirm that two women have been arrested for allegedly assaulting a security guard near Harvil Road.
They have been taken to a police station for questioning.
Road reopened and protesters still in place
Following a temporary road closure at the Harvil Road HS2 site, the road has now been opened again and the protesters are still in place.
Police find no evidence of wildlife crime
Police attending the Harvil road site to investigate a wild life crime reported by HS2 protesters this morning have found there is no evidence to the claim.
A police spokesperson said: “Police received an allegation of wildlife crime on Tuesday, 3 October in relation to activity at a site near Harvil Road, Uxbridge.
“Officers assessed the information provided and spoke to parties involved.
“No evidence of a crime was established. No further police action at this time. “
Photo shows protesters staying put
While police and bailiffs have arrived at Harvil road to remove HS2 protesters an image shows Sarah Green and protesters blocking the digger are staying put.
Stand off continues and road block in place
The stand-off between bailiffs and HS2 protesters continues at Harvil road.
The road has been blocked for the last 20 minutes as police await more officers to remove protesters.
Video footage shows a police officer speaking to a group of campaigners gathered at the site, telling them to leave.
With two police cars present protesters show no sign of moving.
Bailiffs arrive to remove protestors
Bailiffs have arrived at the site to remove protesters.
Footage shows police and bailiffs arriving at the site where Sarah Green and anti HS2 protesters have been gathering since yesterday.
Video footage shows digger stalled at HS2 site
Video taken at the Harvil Road site shows workmen waiting around the stalled digger that protester Sarah Green is lying under.
Anti HS2 campaigners have gathered at the side of the road to show support for Sarah and continue the protest.
Bailiffs are awaiting a court order to remove protesters from the area.
Statement from HS2
A statement released by HS2 on Monday (October 2) said:
Harvil Road site forms part of the early works programme preparing the route for the construction of the railway.
We have ownership of the land and permissions to undertake works on the site.
At the time, a spokesman for HS2 said:
The safety of the local community and our people remains our main priority.
Picture shows tarpaulin which has been erected at the front of the site
'There are, I guess, 25 odd security guards and about eight or nine bailiffs hanging around'
Mark Keir, co-ordinator for Hillingdon Green Party describes the latest from the scene:
That front area by the road side has been cleared, there are, I guess 25 odd security guards and about eight or nine bailiffs hanging around.
They’re still under the digger and I think they are still waiting for a court orders to do anything about that.
'We've been here all night'
Sarah Green who has been under the digger for around 24-hours spoke to getwestlondon:
We’ve been here all night, there’s five of us, we’ve been surrounded by an inner fence.
We’re occupying the digger and where the digger is and the security here are being very good, but they have actually erected an inner fence and they’ve out a tarpaulin up so we can’t be seen from the road and they’ve put a tarpaulin up with fencing along the road as far as we know.
We can’t really see what’s going on there but we know there’s quite a lot of noise.
Video from the scene on Monday
Mark Keir, co-ordinator for Hillingdon Green Party explains why there is a protest
'They have fenced around the digger'
Alice Greenham, daughter of lead protestor Sarah Green, spoke to getwestlondon:
They have moved the outer perimeter fencing forward so that the protestors and supporters are no longer able to stay outside.
They have fenced around the digger - all fencing with blackout netting.