Six fire engines and 35 firefighters have extinguished a fire at a farm on Whitewebbs Road in Enfield.
Two barns – one of them 90 feet long – a number of farm out buildings and a flat bed lorry were alight.
Crews have also cooled two propane cylinders which were involved in the blaze.
Station Manager Steve West said:
When they arrived our firefighters were faced with two open sided Dutch barns and a number of farm out buildings which were well alight.
Thankfully farm workers had managed to lead around 30 pigs and seven dogs to safety before we arrived. Our crews worked hard in hot and challenging conditions to get the fire under control.
Firefighters from Enfield, Finchley and Edmonton fire stations along with firefighters from Hertfordshire fire and rescue service are at the scene.
The Brigade was called at 3.30 pm yesterday afternoon and the fire was under control by 7.23 in the evening.
The cause of the fire is under investigation.