Gaza, Aug 25 (Xinhua) Three Palestinian brothers were killed early Tuesday in an Israeli airstrike at smuggling tunnels in southern Gaza Strip town of Rafah, witnesses and medical sources said.

The latest incident intensified violence that flared up in the Gaza Strip suddenly, ending months of quiet between Palestinians and Israeli army and opening the door for a possible escalation.

Three other people were injured when Israeli fighter jets dropped two bombs at the border between Rafah and Egypt, targeting the underground tunnels, the sources added.

The witnesses said more people have gone missing in the sudden raid, and hundreds of people and rescue workers gathered in the area to dig out the dead bodies and the missing workers.

The tunnels are used to bring in a wide array of products that are no longer allowed through official crossing points due to an Israeli blockade that has been in place for more than two years.

Israeli media quoted army officials as saying that the bombing was in response to Monday mortar attack from the Gaza Strip. An Israeli soldier was lightly injured when three mortars hit southern Israel. No one has claimed responsibility for the attack.