KYIV -- Upon hearing a long, protracted siren, all citizens at home should turn on their radios, learn the location of the nearest bomb shelter, and inform their neighbors.

They should then close all their windows, turn off the gas and water supply at the mains, gather up necessities including personal medication, and walk without panicking to the shelter indicated. Those not at home should take shelter in the city's cavernous underground subway system.

These instructions on how to act in the event of a military emergency were posted on notice boards across the Ukrainian capital overnight on April 15-16, heightening fears that Russia might invade.

"ATTENTION EVERYBODY! Sirens and a continuous ringing sound from other signal devices indicate a communication on civil defense," they read.

The notices were then abruptly taken down less than a day after their appearance.

"There was an order to take them all down," a street sweeper removing the notices in downtown Kyiv told RFE/RL.

It is unclear why the notices were removed, although pedestrians speculated it was so as not to scare residents.

The notices, and their removal, was just the latest sign that interim authorities in Kyiv are jittery about a possible Russian invasion -- but unsure what to do about it.

Bomb Shelters

For months, the authorities in Kyiv have been taking tentative steps to prepare for a possible Russian invasion.

In late March, with mounting speculation of an imminent Russian invasion, Kyiv authorities carried out inspections on over 526 bomb shelters and said they were working on a new siren warning system.

Volodymyr Bondarenko, chairman of the Kyiv city administration, told RFE/RL’s Ukrainian Service on March 27 that the most effective shelters could provide safety for 1.5 million residents.

Vika Libash, a mother of two in Kyiv, welcomed the notices in the capital. "I think it’s the right thing to do so that people know what to do in the event of a siren or signal," she said. "I really think it’s important so that there isn’t panic. You need to do it for schoolchildren as well.”

Libash added that the notices were probably taken down because they were jarring and unusual for younger residents of the capital. But she recalled how, in her youth, she was constantly being warned of an impending war.

Of course, back then, she laughed, in the 1970s, the enemy was the United States.