Tel Aviv  - Israeli fighter jets flew another sortie over the southern Gaza Strip's border with Egypt around sunset Tuesday, bombing a series of smuggling tunnels, military officials said.

Already earlier in its air campaign against Hamas which was launched on Saturday, the Israeli army said it had destroyed as many as 40 tunnels in a matter of minutes as planes dropped bombs on them.

The vast network of tunnels under the border town of Rafah is used to smuggle goods and weapons into the strip, circumventing a tight Israeli blockade.

The Israel Defence Forces (IDF) meanwhile denied reports that it had advised the Israeli government to observe a 48-hour unilateral ceasefire before continuing the offensive, and study Hamas' reaction.

Operation "Cast Lead" is continuing according to the guidelines approved by the Israeli security cabinet last week, a spokeswoman told Deutsche Presse-Agentur dpa. "There is no ceasefire." (dpa)