Metro Evacuated In Warsaw
Warsaw authorities evacuated the city's only underground line on Tuesday following a bomb threat, but the mayor said he suspected the threat was a hoax.
Poland heightened security at train and bus stations, airports and the Warsaw underground after last week's attacks on London's transport system which killed at least 52 people.
Officials said bomb squads had searched half of the 16 stations but had found no explosives so far.
"It looks like a false alarm, but there was no guarantee at the time," Warsaw mayor Lech Kaczynski said.
Warsaw's underground has only one line, linking the city's northern and southern suburbs.
Alongside Britain, Poland is part of a U.S. coalition in Iraq, where it has about 1,700 soldiers. Another U.S. ally, Denmark, has evacuated several Copenhagen underground stations three times in recent days due to threats.