The Israeli army on Thursday rounded up 33 Hamas political leaders in the West Bank, including cabinet ministers, parliamentarians and mayors, to exert pressure on the movement’s militants in the Gaza Strip to stop firing rockets at southern Israel.

Unlike the elusive rocket squads in Gaza, the political leaders in the West Bank are sitting targets in a territory that is under Israel’s security control.

“Arrests are better than shooting,” Amir Peretz, defence minister, told Army Radio. He said he hoped the arrests would send a signal to military wings of organisations involved in the rocket fire.

The army offered an alternative motive, saying Hamas was involved in enhancing a terror infrastructure in the West Bank on the Gaza model and was using government institutions to support terror activity.

Last year, the army carried out a similar round-up after militants captured an Israeli soldier near the Gaza Strip border. Corporal Gilad Shalit is still missing and 40 Hamas parliamentarians detained at the time – about a third of the PA assembly – are still in jail.

The most senior of those held on Thursday was Nasser Shaer, Palestinian Authority education minister. Others included the mayors of the West Bank towns of Nablus and Qalqilya.

Palestinian moderates believe a surer way of ending the present violence lies in a restoration of a ceasefire between the militants groups and Israel. Mahmoud Abbas, the PA’s Fatah president, was on Thursday trying to persuade militant groups to end the rocket fire, which he described as “pointless”.

Hamas, however, has said it will not renew a truce that came into force six months ago unless Israel extends it to the West Bank, the scene of nightly raids and arrests by Israeli security forces.

Four rockets were fired into Israel early on Thursday, the latest of some 200 launched in just over a week. No injuries or damage were reported.

In a number of air strikes on Thursday, Israeli forces targeted the offices of two money-changers in Gaza City alleged to be involved in transferring foreign funds to militant organisations.