Palestinian rockets thudded into southern Israel yesterday in the latest round of tit-for-tat fire across the Gaza border.

“There were two rockets that were fired in the general direction of one of the kibbutzim,” police spokesman Micky Rosenfeld said, without reporting damage or injuries.

Earlier, three other unspecified “projectiles” were fired from Gaza into southern Israel, also causing no casualties, the military said. A spokeswoman was unable to say if they were also rockets, or mortar rounds.

On Wednesday, Israeli jets bombed three sites in the Gaza Strip in response to rocket fire from the coastal strip earlier the same day, Palestinian officials and the military said. The airstrikes were the second in as many days, as rocket fire from Gaza into Israel increased after months of relative quiet.

The military said its aircraft targeted three tunnels, two used for smuggling in southern Gaza and one “used for terrorist activity” in the north of the Palestinian territory.

“The tunnels were targeted in response to the firing of rockets at Israel’s southern communities during the previous day,” the military said.

Palestinian medical sources said five people were moderately wounded in the strikes and two people were reported missing.

The Israeli strikes overnight came after similar air raids a day earlier.

The military said those strikes targeted two “weapons manufacturing sites” in northern Gaza. Palestinian medical sources said one woman was moderately injured in the raids.

The rocket fire and retaliatory raids represented the first significant uptick in violence in the area since April, when tensions rose after an anti-tank missile fired from Gaza hit an Israeli school bus, killing a teenager.

Israel responded with a series of airstrikes that killed at least 19 Palestinians in the deadliest violence since Israel’s devastating 22-day assault on the Gaza Strip in December 2008-January 2009.

The violence raised fears of another such assault, but on April 10 the Hamas rulers of the Gaza Strip declared a return to the truce that ended Israel’s “Operation Cast Lead” in January 2009, and the calm has since largely held.