London ? Authorities evacuated a terminal at London’s Heathrow Airport for about four hours on Tuesday after a man dropped off a package near the Air Algeria and Lufthansa desks and ran away, airport staff members said.

One man was in custody in a West London police station, authorities said. Police would not discuss the contents of the package.

About 2,000 people were ordered out of Terminal Two, which houses many European carriers, about 1 p.m., police said.

In August, police said they thwarted a plot to blow up flights traveling between Britain and the United States. The plot touched off stricter security measures at all British airports, prompting travel chaos at Heathrow for weeks.