Israeli army arrested four Palestinians in the West Bank and sent troops to the south of the Hamas-ruled Gaza Strip on Thursday.

Unnamed Palestinian security sources in the West Bank said the Israeli forces raided Bethlehem City, launching door-to-door search operations and arresting four Palestinians.

An Israeli army spokesperson earlier told the Israel Radio that the four Palestinians were wanted by the Israeli security and are now being interrogated.

The Israeli army troops burst into the West Bank cities repeatedly and arrest Palestinians alleged to be "wanted activists. " However, the Western-backed Palestinian National Authority (PNA) said these attacks hold back its security forces to enforce law and order in the territory.

Meanwhile, the Israeli land troops, backed by tanks and bulldozers, advanced into the southern Gaza Strip town of Khan Younis, destroying fields in the area, witnesses said.

Rounds of heavy gunfire were heard as the troops advanced, yet no injuries were reported, witnesses from the area told Xinhua.

The Islamic Hamas movement seized control of the Gaza Strip by force in 2007.

The Israeli army enforces a 300-meter-wide no-man zone alongside the Gaza-Israel border to stop militants from firing rockets against neighboring Israeli towns.