Estonia has accused Russia of ordering an arson attack on the Milrem Robotics defence plant, in one of the Baltic state’s most serious security allegations against Moscow. Officials said the fire was set deliberately as part of a wider campaign against European defence suppliers.

The blaze broke out at the facility outside Tallinn earlier this week. Fire crews brought it under control, and no casualties were reported. Police quickly treated the case as suspected arson and made arrests, according to Estonian media.

Milrem Robotics builds unmanned ground vehicles used by several NATO armies. Estonia’s security service said the attack fits a pattern of sabotage attempts linked to Russian intelligence across Europe, a claim Moscow has denied.

The incident has raised fresh alarm among NATO members. Estonia has stepped up security around critical infrastructure and urged allies to share intelligence on sabotage networks. Investigators say the probe is ongoing. Milrem’s robotic vehicles are in service with more than a dozen countries, and the company has expanded rapidly since the Ukraine war began.