A suspicious tyre fire caused $10,000 damage at Iveco in Dandenong South a year after a similar blaze threatened the truck factory.
Police and CFA crews were called to the fire at the Princes Highway site just after 4.30pm on Sunday 12 November.
Greater Dandenong CIU Detective Senior Constable Damien Wigfield said it appeared someone had deliberately lit pallets containing truck tyres and rims after entering through a side security gate.
On 3 December last year, security staff reported a fire at the same site to emergency services about 4.45pm and CFA crews brought the fire under control about 7.10pm.
Police also deemed that fire to be suspicious.
Call Crime Stoppers on 1800 333 000 with information.
