In late May 1982 Special Air Service patrols from G Squadron found that a number of high peaks overlooking the Argentine defences around Port Stanley were largely undefended, after the Argentine heliborne reserve 'Combat Team Solari' (B Company, 12th Infantry Regiment) had been dispatched to support the fighting at Goose Green and the 4th Infantry Regiment had received orders to abandon Mount Challenger and take up positions on Mounts Two Sisters and Harriet.

The first engagement occurred during the night of the 29–30 May 1982 when the 3rd Assault Section of 602 Commando Company, led by Captain Andrés Ferrero, ran into Air Troop from D Squadron, 22nd SAS, on the slopes of Mount Kent, sustaining one badly wounded (First-Sergeant Raimundo Viltes), abandoning much of its equipment to the anger of Major Aldo Rico, their Commanding Officer.

[11] First Lieutenant Rubén Eduardo Márquez and Sergeant Oscar Humberto Blas were both killed and showed great personal courage in the firefight[12] and were posthumously awarded the Argentine Nation to the Valour in Combat Medal.

[18] On the night of 30 May, Captain Peter Babbington's K Company of 42 Commando, Royal Marines and a supporting field artillery battery boarded three Sea King helicopters and the surviving RAF Chinook (Bravo November) and moved forward from San Carlos.

At about the same time, the 2nd Assault Section under Captain Fernández, having hidden all day, emerged from their hides intending to withdraw from the area under the cover of darkness but came under prompt and heavy fire from Mountain Troop.

One of them, responding to a call for help from D Squadron SAS, was badly damaged by small arms fire while attacking Mount Kent's eastern lower slopes.

Sub-Lieutenant Llambías-Pravaz's platoon was later credited with the destruction of Harrier XZ963 flown by Squadron Leader Jerry Pook[25] with another claim going to 35 mm Oerlikons of the 601st Anti-Aircraft Artillery Group under the command of 2nd Lieutenant Roberto Enrique Ferre that had been moved forward to cover the retreat of the 4th Regiment that had been occupying Mount Challenger, according to Captain José Fernando Trindade from the 601st Air Defence Artillery Group.

"[30] This is corroborated by Marine First Corporal Jacinto Eliseo Batista in the lead transport that says the Fokker had to practically abort the landing while flying over the runway that was under heavy naval bombardment.

[32][33] The Special Air Service won praise for defending Mount Kent and the surrounding peaks, the citation for the Distinguished Service Order won by Major Delves: Following the successful establishment of the beachhead in San Carlos Water, Major Delves took his squadron 40 miles behind enemy lines and established a position overlooking the main enemy stronghold in Port Stanley where at least 7000 troops were known to be based.

By a series of swift operations, skilful concealment and lightning attacks against patrols sent out to find him, he was able to secure a firm hold on the area after ten days for the conventional forces to be brought in.

Mount Kent would come under sporadic but intense Argentine long-range 155 mm artillery fire with Kim Sabido from Independent Radio News reporting on 31 May, "For me it was just another version of hell and the shower of shrapnel which accompanied each explosion was just a reminder of how close to the margins of life these men are now fighting.

Had D Squadron not been there, the Argentine Special Forces would have caught the Commando before de-planing and, in the darkness and confusion on a strange landing zone, inflicted heavy casualties on men and helicopters.

[37]A Scorpion tank from the Blues & Royals helped clear Mount Kent from the remaining Argentine special forces and engaged the 4th 'Monte Caseros' (Jungle) Infantry Regiment troops digging in on the lower slopes of Two Sisters Mountain, opposite Murrell River.

[40] With 23 Troop thinly spread in the forward British lines, the 3rd Assault Section from 602 Commando Company was able to return to the area on the night of 3–4 June, reaching the summit of Mount Challenger after a difficult approach.

Upon returning to Port Stanley, Major Aldo Rico along with First Lieutenant Jorge Manuel Vizoso-Posse, (second-in-command of Ferrero's patrol) tried to convince Brigadier-General Oscar Jofre to helicopter forward a rifle company in order to attack the recently arrived British artillery batteries the commandos claimed to have located using their night binoculars, but an irritated Jofre told them to go and leave the decision-making process up to 10th Brigade Headquarters.