A Palestine Action activist who struck a police officer with a sledgehammer during a protest at an Israeli-linked arms factory acted to protect a co-defendant he believed was being seriously hurt, a court has heard.

Samuel Corner, 23, is accused of causing grievous bodily harm with intent to Sgt Kate Evans during a raid on the Elbit Systems facility, in Filton, near Bristol, on 6 August 2024.

Alongside Charlotte Head, 30, Leona Kamio, 30, Fatema Rajwani, 21, Zoe Rogers, 22, and Jordan Devlin, 31, Corner is also charged with criminal damage, with respect to the destruction of drones, computers and other equipment.

The trial at Woolwich crown court has previously heard that Corner hit Evans in the back with the sledgehammer – while she was on all fours, facing away from him, attempting to arrest Rogers – fracturing the officer’s spine.

On Wednesday, Corner, who is autistic and squeezed an anti-stress toy while giving evidence, said that before he struck Evans he was anxious, scared and panicked, having been sprayed “straight in the face” with Pava spray (similar to pepper spray) and heard his co-defendants screaming.

He said he had also been taken aback by the presence of security guards on the factory floor as he was told beforehand that they would not attempt to confront the activists.

Asked by his barrister, Tom Wainwright, why he swung the sledgehammer at Evans, Corner replied: “To protect. I heard someone screaming … and I thought she was being seriously hurt by security.”

The barrister asked Corner what he had hoped to achieve in “bringing the sledgehammer down in the way you did”.

In response, he said: “To protect her.”

He added: “I would never want to seriously hurt anyone.”

The former University of Oxford linguistics and philosophy student said he was “very scared, especially for the others”.

Corner, who has been held in prison since being arrested on 6 August 2024, also said that he did not realise that police officers had arrived as opposed to just security guards. He told the court he had never been arrested, been in a fight nor used violence prior to the incident at the Elbit factory.

Asked by Wainwright what the intention of the action was, Corner said: “We intended to destroy weapons and things needed to make weapons which we believed were going to be used to cause death and destruction. We wanted to shut Elbit down, shut this facility down for as long as possible so they couldn’t make or export weapons from there.”

In cross-examination, prosecutor Deanna Heer KC asked Corner whether as an “intelligent person” he would know that a sledgehammer was capable of causing “really serious harm”.

He replied in the affirmative, but added: “When I did this I was panicking, I was in pain, I’d just been pepper sprayed.”

Heer also asked him about his reaction when arrested for grievous bodily harm, suggesting it should not have come as a surprise to him. But Corner told the court: “I was shocked and scared because I wasn’t expecting to be arrested for that and I wasn’t trying to cause serious harm to anyone. It wasn’t something I ever saw myself doing or being arrested for or being associated with.”

Corner will resume giving evidence on Thursday after Wednesday’s proceedings had to be cut short because he felt unwell.

The defendants deny all the charges. The case continues.