British troops in Afghanistan have carried out one of the biggest air operations of modern times, the Ministry of Defence said.

Operation Panther's Claw, an assault by Scots soldiers on one of the last Taliban strongholds in Helmand Province, began just before midnight on Friday.

Twelve Chinook helicopters, supported by 13 other aircraft including Apache and Black Hawk helicopter gunships and Harrier jets, dropped more than 350 troops from the Black Watch into Babaji, north of Lashkar Gah.

The aim was to secure a number of canal and river crossings to establish a permanent International Security Assistance Force (ISAF) presence in what was previously a Taliban stronghold.

The troops were followed by Royal Engineers and explosive teams who spent the last two days building checkpoints — soon to be permanently occupied by the Afghan National Police — on the main routes in and out of the area to hinder movement by insurgents.

The insurgents launched a number of attacks against the Black Watch but each was fought off and the Scottish troops have secured three main crossing points: the Lui Mandey Wadi crossing, the Nahr-e-Burgha canal and the Shamalan canal.

They also found 1.3 tonnes of poppy seed and a number of improvised explosive devices and mines before they could be laid.