Palestinian militants in the Gaza Strip on Wednesday fired three mortar shells into the western Negev in southern Israel, Israel Army Radio reported.

The shells exploded in the Sha'ar Hanegev region, causing neither casualties nor damage, said the report.

Over the last weekend, the Israel Air Force bombed five tunnel systems used for smuggling arms and other goods from Egypt into Gaza, as a response to renewed rocket and mortar fire from the coastal enclave into Israel.

In late December, the Israeli army launched a 22-day-long military offensive in the Palestinian enclave in response to continued rocket attacks at southern Israel, leaving over 1,300 Gazans and 13 Israelis killed.

The two sides separately staged their ceasefire in mid-January, yet sporadic flare-ups of violence continued in recent months, and Egypt-brokered negotiations over a long-term truce has so far seen no progress.