Operation Diesel was a raid by 700 British troops from the Royal Marines 45 Commando, 42 Commando, and the 3 Commando Brigade's Reconnaissance Force, as well as armoured infantry and close reconnaissance from 1st Battalion Princess of Wales's Royal Regiment (1 PWRR) on a Taliban drug factory and arms stronghold in the Upper Sangin Valley in Helmand province, Afghanistan on February 7, 2009.