As the worst violence in years rages between the Israeli military and Hamas, each night the sky is lit up by a barrage of missiles streaking across the sky and the projectiles designed to counter them.

It is a display of fire and thunder that has been described as both remarkable and horrifying.

The images of Israel’s Iron Dome defense system attempting to shoot down missiles fired by militants in Gaza have been among the most widely shared online, even as the toll wrought by the violence only becomes clear in the light of the next day’s dawn.

“The number of Israelis killed and wounded would be far higher if it had not been for the Iron Dome system, which has been a lifesaver as it always is,” Lt. Col. Jonathan Conricus, an Israeli military spokesman, said this week.

The Iron Dome became operational in 2011 and got its biggest first test over eight days in November 2014, when Gaza militants fired some 1,500 rockets aimed at Israel.

While Israeli officials claimed a success rate of up to 90 percent during that conflict, outside experts were skeptical.

The system’s interceptors — just 6 inches wide and 10 feet long — rely on miniature sensors and computerized brains to zero in on short-range rockets. Israel’s larger interceptors — the Patriot and Arrow systems — can fly longer distances to go after bigger threats.

The Iron Dome was recently upgraded, but the details of the changes were not made public.

It is being tested like never before, according to the Israeli military.

“I think it will not be a big mistake to say that even last night there were more missiles than all the missiles fired on Tel Aviv in 2014,” Major General Ori Gordin, commander of Israel’s home front, said during a news conference on Sunday. “Hamas’s attack is very intense in terms of pace of firing.”

Militants in the Gaza Strip have fired nearly 3,000 missiles, the Israeli Air Force said on Sunday, noting that about 1,150 of them had been intercepted.

“Despite the layers of defense, there is never 100 percent defense,” Gen. Gordin said. “Sometimes the aerial defense will miss or not be able to intercept, and sometimes people will not get into shelters or lay on the ground and sometimes a whole building will collapse.”