A Qassam rocket is displayed in Sderot town hall against a background of pictures of Israeli residents killed in rocket attacks. Photo: Tom Spender via Wikimedia Commons.

Jerusalem Mayor Nir Barkat on Tuesday evening instructed residents to open and prepare public and private bomb shelters, due to increasing Hamas rocket fire out of Gaza.

Residents of the city and its environs have about 90 seconds to seek shelter in the event of a rocket attack out of the southern coastal enclave.

“A list of shelters will be published on the municipality website later this evening,” the city said in a statement.

“In the case of a siren or explosion, residents should go to the closest protected area within a minute and a half and close all doors and windows and stay indoors for 10 minutes,” officials said.

“All residents are asked to continue to listen to instructions from the Home Front Command. As of now, all municipal events will take place as scheduled.”

Israeli municipalities in the densely-populated Gush Dan region also told residents to make similar preparations.

This is the first time since 2012’s Operation Defensive Shield that rocket fire was expected to hit the capital.

In that operation, Hamas fired volleys of rocket that hit to the southeast of Jerusalem, in the Gush Etzion bloc of communities.

Tuesday’s measure comes after a Palestinian rocket attack on Tel Aviv and areas between Israel’s two largest cities earlier in the day.

An Iron Dome battery downed a long-range Iranian M-75 rocket in the vicinity of Ben-Gurion International airport, according to Israel’s Ynet news site.

There were no casualties in the barrages.

Earlier, the IDF confirmed downing a rocket over Gedera, 25km south of Tel Aviv. The projectile was part of a large volley of rockets fired by Hamas towards the southern edge of central Israel, according to The Times of Israel. Sirens and explosions were heard across the south.

“Due to (Israel Air Force) activity, Israel’s civilian air traffic corridors have been narrowed which could result in delays for takeoffs and landings,” Israel’s Airports Authority told The Algemeiner in a statement.

Israeli counter strikes across Gaza have killed some 16 terrorists and non-combatants and wounded close to 100, Palestinians said.

Palestinian news sites showed scores of Gazans standing on rooftops, serving as human shields, which added to the chances of them being hit in IDF strikes on Hamas and Islamic Jihad facilities.

Referring to the ongoing Israel Air Force operation, Defense Minister Ya’alon said earlier that “Our aim – zero rockets. The situation on the ground has proven that Hamas does not want a truce.”

“I told mayors in the Tel Aviv Metropolitan Area to take into account possible fire on their cities,” he added.