Two Just Stop Oil protesters have denied causing at least £52,000 worth of damage after private jets were sprayed with orange paint at Stansted Airport.

Cole Macdonald, 22, of Brighton, and Jennifer Kowalski, 28, of Dumbarton in Scotland, pleaded not guilty at Chelmsford Magistrates’ Court on Saturday to causing criminal damage and interfering with national infrastructure.

The pair are accused of using angle grinders to break through an airport fence at around 5am on Thursday before entering a taxiway with Just Stop Oil-branded fire extinguishers filled with orange spray paint, the court heard.

The pair, who appeared in court via videolink from Chelmsford police station, are then alleged to have sprayed two jets.

Prosecutors say that the cost of cleaning up the paint was £52,000, although the full damage to the fence and amount needed to fund extra security in the wake of the alleged stunt is not yet known.

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The court heard that thousands of passengers were impacted as 75 flights were disrupted during a 38-minute delay.

Kowalski and Macdonald are also both charged with aggravated trespass, though they were not asked to enter pleas for that.

The pair were remanded in custody to appear at a plea and trial preparation hearing at Chelmsford Crown Court on July 22.

One supporter swore loudly from the public gallery after they were denied bail.

Environmental group Just Stop Oil said activists had entered the airfield and used fire extinguishers filled with orange paint.

Essex Police said it detained two people after they gained access to a private area of an airfield and were “causing damage to two aircraft”.

The force confirmed the private jet of pop star Taylor Swift, which Just Stop Oil said had landed at Stansted “mere hours before”, was not at the airport.

Swift is performing at Wembley Stadium this weekend as part of her Eras tour.