Two protesters have blocked the road outside Rathlin Energy’s exploration site at West Newton in East Yorkshire for about 20 hours.
The pair locked their arms together through a reinforced concrete tube on Pipers Lane, the road leading to the site.
The protest began at about 4am this morning.
Police have not attempted to release the protesters or make arrests.
Operations at the site have continued. Rathlin Energy is drilling a second well at the site to explore for oil and gas.
Update: The protesters were released by a specialist police team at about 2am on 5 June.
This is the most recent of a series of protests staged by opponents of operations at the West Newton site.
Last month, a lock-on protest in the site entrance continued for more than 50 hours. Two people were later charged with obstructing the highway and obstructing a police officer (details).
In April, another lock-on protest closed the road to the well pad for eight hours. Police left the scene in mid afternoon and the road reopened when the protesters released themselves. There were no arrests (details).