Armed officers who rushed to the scene of the London Bridge attacks kept firing at wounded terrorists on the ground, fearing they were wearing explosive suicide vests and were trying to detonate them, the inquest into the deaths of their eight victims has heard.

Dramatic evidence of the carnage wreaked by the three attackers and how police stopped them emerged on the second day of evidence at the inquests at the Old Bailey in London on Wednesday.

The three attackers hunted as a pack for their victims. After storming one restaurant where they stabbed people, the ringleader – Khuram Butt, 27 – rinsed blood off his knife under a tap, then wiped it on his beard in what Jonathan Hough QC, counsel to the inquest, described as a “chilling gesture”.

The three attackers first mowed down pedestrians with a van on London Bridge, before going on a rampage armed with knives, in and around Borough Market, on 3 June 2017. They were also wearing what appeared to be bomb belts which were subsequently found to be fakes.

The inquest heard that the three terrorists rushed at the first armed police on the scene, from the City of London force, who shot them. The confrontation happened outside the Wheatsheaf pub, where staff had barricaded customers inside.

Det Supt Rebecca Riggs of Scotland Yard’s counter-terrorism command, who led the investigation into the attacks, said armed officers still feared the terrorists, by then on the ground, could kill after being shot and “believed they were wearing suicide devices and maintained cover from a distance”, meaning they kept their weapons trained on the suspects.

They used their police vehicles as “hard cover” to protect them in the event of a blast. Officers then fired more shots.

Riggs said: “They could see they were moving, they believed they were going to activate explosive devices they were wearing so they fired further shots.”

Video shown in court showed movements from the terrorists as they lay on the ground, with police firing further shots into their bodies.

Officers, still believing the suicide belts could be detonated, risked their lives, using a ballistic shield as cover, to evacuate the pub, Riggs said.

However, in the fusillade of bullets in the confined area, one customer in the pub was hit in the head by a bullet and survived. Five other civilians were struck by shrapnel.

Police suspected there could be two groups of attackers. After starting their attack, the terrorists removed their outer clothing, so the three who had been shot bore little resemblance to the description the police had first received.

Even after the terrorists were shot, police feared explosions and that other attackers were on the loose.

A public “run, hide, tell” message was issued as police were conscious the attack could continue.

Riggs said police policy was to declare the scene of the attack, including where the terrorists lay, a “hot zone” open only to armed officers. But the officer in charge at the scene, Supt Roy Smith, suspended the policy because seriously injured civilians needed urgent medical help.

“They could see there were members of the public who were at risk and needed evacuating,” Riggs told the inquest.

From the beginning of the attack to the terrorists being shot took 10 minutes, with all the killings happening in the first three minutes.

Police fired close to 50 bullets at the three attackers: Butt, on MI5’s radar at the time of the atrocity, Rachid Redouane, 30, and Youssef Zaghba, 22.

CCTV footage was shown of the terrorists forcing open doors of the Black and Blue restaurant before attacking those inside. One man was stabbed several times, and another forced to the ground and stabbed.

Almost every second of the 10-minute attack was caught on camera, on CCTV or mobile phone, sometimes from multiple angles.

The footage revealed grotesque scenes and was greeted in court with gasps as families of the victims watched. During the stabbing spree, one terrorist stopped to bend down and tie his shoelaces.

Saturday night revellers in the area were seen reacting in different ways: some fled, some stood and watched as the carnage unfolded. Footage showed a man who had been stabbed throwing his drink at the attackers, while another man threw a chair at them.

Those who died were Chrissy Archibald, 30, from Canada, Sebastien Belanger, 36, a chef, Kirsty Boden, 28, a nurse from Australia, Ignacio Echeverría Miralles De Imperial, 39, James McMullan, 32, the only Briton, who was from Brent, north-west London, Alexandre Pigeard, 26, a French restaurant worker, Xavier Thomas, 45, a French national and Sara Zelenak, 21, an Australian national.

The inquest continues.