kabul crater
© Reuters
A Briton was killed and several wounded in a Taliban assault on the compound of a UK security company that left six dead.

A car bomb outside the G4S compound in east Kabul was followed up by attackers on foot who managed to get inside the building.

Five of the company's staff were among the dead, including a Briton and four Afghans, in an attack claimed by Taliban insurgents.

Several hundred people are understood to have taken refuge in bunkers as Afghan army commandos spent hours trying to clear the compound of attackers.

Local television footage showed a huge crater and widespread damage to buildings after the attack which struck on Wednesday evening.

G4S said another 32 staff were injured in what it called an "unprovoked, criminal attack".

The firm provides security for clients including the British embassy and companies and organisations working in Afghanistan.

A statement from Charlie Burbridge, managing director of G4S Risk Management Group, said "We are committed to our security role in support of the people of Afghanistan, and we are determined that incidents such as this will not prevent the vital work that the international community conducts from happening."

The company's website says it has a purpose-built headquarters in Kabul's Anjuman Secure Business Park. The 26,000 square metre secure compound provides "operational support" for clients and can also provide secure accommodation.

A Taliban spokesman said the group had carried out the attack. Both the Taliban and the Islamic State group have stepped up their attacks on Kabul, which is one of the deadliest places in the country for civilians.

G4S is one of the largest private security companies in the world and its staff have come under attack in Afghanistan before. In March, a Taliban car bomb killed at least three people and wounded two in Kabul in an apparent attack on a G4S vehicle.

The suicide bomber had been driving towards the vehicle but "detonated himself before reaching the target", according to officials at the time.

Wednesday's attack came just hours after Afghan President Ashraf Ghani announced his team for prospective peace talks with the Taliban, as the United Nations renewed calls for direct negotiations between Kabul and the militants.

At an international conference on Afghanistan in Geneva, Mr Ghani said his 12-person negotiating team includes both men and women and will be led by his chief of staff Abdul Salam Rahimi.

On Tuesday, three US soldiers were killed in a blast near Ghazni city in central Afghanistan that was also claimed by the militant group.

The attacks come at the end of what is likely to be the bloodiest year of the West's 17-year-long to support the Afghan government against Taliban insurgents and the newer threat of Isil.

Casualties among both Afghan forces and civilians have reached record levels, while Taliban control of rural districts is undiminished. Kabul has become a focus for much of the violence in recent years.

Last week at least 55 people were killed when a suicide bomber detonated during a meeting of clerics in a Kabul meeting hall.