Kabul: An elite unit of British paratroopers and Royal Marines has been carrying out secret raids on Taliban fighters and supply lines months after ministers and generals announced that British troops had stopped offensive operations in Afghanistan.

An officer of the unit, known as the Special Forces Support Group (SFSG), revealed details of the raids in an Army magazine, commenting that “killing the enemy in the close battle is exactly what we all joined up to do”.

The disclosures in Pegasus, the journal of the Parachute Regiment, come two weeks after reports emerged that 80 British troops had been sent on a secret mission to help Afghan troops to clear Taliban fighters from Sangin.

According to the article, understood to have been written by a senior officer in the unit, the unit’s A Company arrived in Afghanistan in January for a six-month tour and went on to mount relentless raids against the Taliban.

Its strike operations have continued unabated despite government ministers and senior commanders declaring an effective end to British combat operations in Helmand earlier this year.

Brig Bob Bruce, who was commander of British forces in Helmand, said in March: “We have reduced our profile to such an extent that we don’t do ground combat-type operations any more.”

Ministers, who are keen to leave Afghanistan after years of heavy costs and casualties, have stressed that Afghan forces are now in the lead and British troops are only advising them.

The British strike force, which is believed to be up to 150 strong, works hand-in-hand with an elite unit of Afghan commandos, known as Task Force 444, throughout Helmand province.

Photographs with the article, the first ever to detail the highly secretive unit’s work, show the armed British troops boarding US Marine Corps V-22 Osprey aircraft and giant CH-53 helicopters.

The involvement of so many British troops will raise questions over the degree to which Afghan forces are able to stand on their own against the Taliban. Ministers and military chiefs are currently deciding whether British forces will be needed after Nato combat troops leave by the end of next year.

Ministry of Defence sources confirmed that the SFSG and Afghan strike forces led a series of raids on suspected Taliban bomb-makers in May after three British soldiers were killed in a roadside bomb at the end of April. The raids still take place two or three times a week.

“Paratroopers and Marines of A Company continue to work independently with Afghan [commandos] throughout Helmand, delivering outstanding effect above their pay grade,” wrote the officer. “A truly impressive effort that leaves the units they work with shocked that they are “just” privates and marines.”

The unit has targeted insurgent supply lines in the desert near the border with Pakistan, and Taliban bases in the centre of the province. The author commented: “Killing the enemy in the close battle is exactly what we joined up to do.”

The force has taken several casualties.

“The Afghanistan burden is heavy,” wrote the officer. “Our Afghan partners have suffered [soldiers] killed in action and significant injuries in the last 24 months. “[Our] battalion has also shared life-changing injuries in the last 12 [months]. Our thoughts are with all the individuals who have suffered injuries.”