Palestinian militants fired a rocket at southern Israel on Thursday, hours after Israeli warplanes attacked "terror sites" inside the Gaza Strip, the army said.

The rocket fire, which landed in an open field, was claimed by the Popular Resistance Committees in a statement sent to AFP.

Overnight, Israeli warplanes targeted "terror sites" in central and northern Gaza in retaliation after rockets were fired across the border on Wednesday.

"Israeli air force aircraft targeted a terror activity site in the central Gaza Strip, and a terror tunnel in the northern Gaza Strip," a military statement said, indicating it was a response after five rockets landed in Israel, none of which caused any damage or injuries.

Palestinian security sources said the air strikes hit a training ground used by Islamic Jihad militants near central Gaza and another training ground northeast of Gaza which belonged to Hamas's armed wing, causing no casualties.

An earlier series of Israeli strikes overnight Tuesday had killed a Palestinian and wounded about 20 others, as the military targeted what it described as "global jihad" targets who were planning cross-border attacks on southern Israel from the Egyptian Sinai.

Late on Wednesday, a senior Israeli officer said the military was preparing for a possible large-scale military campaign in Gaza if the Palestinians did not halt their rocket attacks.

"We are preparing and ready for an additional campaign... to renew the deterrence," Tal Hermoni, commander of the Gaza division's southern brigade told reporters in remarks widely published in the Israeli press.

Israel's last major operation against Gaza was Operation Cast Lead, a 22-day offensive launched on December 27, 2008 that cost the lives of 1,400 Palestinians -- at least half of them civilians -- and 13 Israelis, including 10 soldiers.