Two anti-HS2 campaigners who recently emerged from tunnels dug near Euston station have had breach of bail proceedings against them withdrawn in court.

Lachlan Sandford, 20, known as Lazer, was taken into police custody after he voluntarily left the network of tunnels beneath Euston Square Gardens in central London on Saturday.

During a brief hearing at Highbury Magistrates’ Court in north London on Monday, breach of bail proceedings against Sandford were withdrawn.

Prosecutor Elgisa Ismaili instead requested to amend the activist’s bail conditions.

According to a court listing document, Sandford’s appearance related to court proceedings at Wycombe Magistrates’ Court in November last year.

A red-headed Sandford, appearing from custody wearing a grey tracksuit and white face mask, spoke only to give his name, date of birth, confirm he had no fixed address and that he understood the proceedings.

His updated bail conditions require him not to interfere with the workings of any HS2 site and not to enter, be present, or remain in any HS2 site or building which is clearly identified as such by way of a sign, fence or other marking.

At least four people are approaching two weeks spent beneath Euston Square Gardens as part of a protest over the impact of the planned high-speed railway.

Protesters have previously claimed the tunnels, dug in secret under Euston Square Gardens, extend for 100ft and that bailiffs had spent hours trying to extract Sandford from a “lock on” at the bottom of a down shaft.

At a separate short hearing on Monday, in a Highbury Magistrates’ youth court, a 17-year-old protester, who was arrested after leaving the Euston protest tunnels, also saw breach of bail proceedings withdrawn by prosecutors.

A spokesman from HS2 Ltd previously said on Friday night that the demonstrator had been detained after she voluntarily left the tunnel.

The teenage activist, who cannot be identified for legal reasons, was supported by her mother in court.

Her bail conditions were also amended and match those set for Sandford.

A Highbury Magistrates’ Court listing document stated that the teenager’s appearance related to court proceedings at St Albans Magistrates’ Court in December last year.

A spokesman for HS2 Ltd has said that the safety of protesters, HS2 staff and emergency services personnel was of “paramount importance”, that it was doing “all we can to end this illegal action safely” and called for activists to exit the tunnels “as soon as possible”.