US intelligence officials warned American defence companies on Thursday to increase security precautions following several acts of sabotage in Europe that officials have blamed on Russia. The public bulletin issued by the National Counterintelligence and Security Centre advised companies involved in defence work ` particularly those providing support to Ukraine in its war against Russia ` to step up their defences in the face of Russia`s escalating aggression toward Ukraine`s allies.

`Russia`s sabotage activities in Europe increase the risk to US companies abroad and potentially at home," the officials wrote in the warning. `Such sabotage operations can sow fear and doubt, damage important infrastructure, disrupt commerce, or cause injury and death.`