GENEVA

Polish authorities have opened an investigation after a train driver was forced to stop due to obstructions placed on tracks near the Suwalki Gap, a strategically sensitive stretch of the Polish-Lithuanian border, local media reported on Thursday.

The driver, who was operating two coupled locomotives without wagons, "stopped, and either removed – or reported – branches, stones and a plank that were blocking the rail," according to differing accounts provided to Polish daily Gazeta Wyborcza.

The incident occurred on Nov. 13 near the village of Raczki in the northeastern Podlasie region. Its location has raised concern because of its proximity to the Suwalki Gap, the narrow corridor between Belarus and Russia’s Kaliningrad exclave that forms the only land link between the Baltic states and NATO members to the south.

Given recent attacks on railway infrastructure elsewhere in Poland, officials have maintained heightened vigilance and a low threshold for regarding unexplained obstructions as possible security threats, TVP World said.

However, police in Suwalki initially treated the case as a minor offence, viewing it as a potential "prank," Gazeta Wyborcza reported. The situation later escalated when Poland’s Internal Security Agency, the domestic counterintelligence service, began monitoring the case after being alerted by local police.

Investigators reportedly are now gathering witness statements and physical evidence. According to Gazeta Wyborcza, officials have only said that inquiries are ongoing and no charges of sabotage have been filed.