Firefighters were attacked with a catapult by a gang of youths as they tackled a raging fire.
The crew was trying to put out the blaze at Gravesend Fencing Ltd in Lower Range Road, Gravesend, at around 6.15pm yesterday.
It is believed they had items thrown at them by the gang and police confiscated what is thought to be a catapult from one of them.
His name and details were taken but no arrests were made.
The fire, not far from an oil and chemicals plant, engulfed the surrounding area in smoke.
Firefighters were called to Gravesend Fencing after a fire started in the yard.
It is not far from the Comma Oil and Chemicals Ltd plant in Dering Way.
Smoke engulfs a neighbouring house
It is not known exactly how the fire started but it caused one of the mobile buildings on site to catch alight with flames believed to have reached up to 50ft.
Witness Tony Matthews called the fire brigade and was shocked by how quickly the drama escalated.
Speaking at the scene he said:"There's thick black smoke billowing out and whole yard is ablaze. The fire is massive.
Firemen try to get into the site
"Flames have gone right across the mobile building now, it's a raging fire.
Mr Matthews said he heard two small explosions.
Smoke could be seen billowing up from beyond the gurdwara
Three fire engines attended the incident.
Crews had to cut through barbed wire to gain access to part of the site.
It's believed around 20 firefighters tackled the blaze.