ZURICH, Switzerland (AP) -- What began as a routine training exercise almost ended in an embarrassing diplomatic incident after a company of Swiss soldiers got lost at night and marched into neighboring Liechtenstein.

According to Swiss daily Blick, the 170 infantry soldiers wandered just over a mile across an unmarked border into the tiny principality early Thursday before realizing their mistake and turning back.

A spokesman for the Swiss army confirmed the story but said that there were unlikely to be any serious repercussions for the mistaken invasion.

''We've spoken to the authorities in Liechtenstein and it's not a problem,'' Daniel Reist told The Associated Press.

Officials in Liechtenstein also played down the incident.

Interior ministry spokesman Markus Amman said nobody in Liechtenstein had even noticed the soldiers, who were carrying assault rifles but no ammunition. ''It's not like they stormed over here with attack helicopters or something,'' he said.

Liechtenstein, which has about 34,000 inhabitants and is slightly smaller than Washington DC, doesn't have an army.