Israeli warplanes have hit southern Gaza with missiles in response to rocket fire from Palestinian militants, the military said.

The airstrikes reportedly hit Gaza's disused Yasser Arafat airport near the border town of Rafah, but no injuries have been reported.

Hamas, which runs the Gaza Strip, says it halted firing rockets after a major Israeli offensive in 2009.

But other Palestinian militant groups have continued to shell Israeli towns.

The Israeli Defence Force says that more than 20 rockets and mortars have been fired at Israeli towns near the border with Gaza this year.

Most of the unguided missiles do not hit their targets.

There have been several Israeli airstrikes in recent months targeting tunnel operators who smuggle goods into the Gaza Strip.

Israel tightened its blockade of the Gaza Strip in June 2007, after Hamas pushed out the forces of its more secular rival Fatah, which the Islamic movement had beaten in elections the previous year.

Israel and Egypt currently deny entry into Gaza for all but the basic humanitarian supplies.