Gaza Strip ? For the first time since its pullout from Gaza a year ago, Israeli tanks and infantry took up positions on the Egypt-Gaza border Wednesday, killing two Palestinian gunmen as the army broadened its search for arms smuggling tunnels.

Palestinian security officials said Israeli troops and tanks moved into the border town of Rafah before dawn Wednesday and took over a section of the frontier, including the area around the Rafah border terminal.

The army said Israeli forces were pressing an operation aimed at uncovering tunnels used by Palestinian militants to smuggle weapons from Egypt. The army said Wednesday it has uncovered five tunnels so far.

Israel has sent tanks and troops in and out of Gaza and stepped up airstrikes against suspected militants and weapons caches since Hamas-linked militants tunneled under the border in late June and attacked an Israeli army post, killing two soldiers and capturing another, Cpl. Gilad Shalit.

On Wednesday morning, Israeli troops killed two Hamas militants as they approached army positions in Rafah, the army and Palestinians said. Hamas said in a statement one of the two was a senior militant involved in Shalit’s abduction.