A senior Palestinian security officer said police raiding the West Bank town of Dura, south of Hebron, also arrested 16 suspects in the start of a new Palestinian Authority crackdown on lawlessness.
While the action seemed a move towards meeting the demands of Israel and a US-backed "road map" peace plan for Palestinians to disarm resistance groups, it was not clear whether any weapons seized had belonged to the groups involved in attacking Israel.
Palestinian President Mahmud Abbas has vowed to end armed chaos in the Palestinian territories, but has previously sought to do so through dialogue with resistance groups rather than use force.
Jihad Abu Umar, a senior Palestinian security official in Dura, said that those targeted in Dura were "fugitives of the law" suspected of torching three Palestinian Authority vehicles and stealing cars.
Violence between armed groups
and Palestinian security is up
"More than 120 Palestinian security officers from all the security forces began a campaign to put an end to the chaos ... criminals and those who have vandalised public institutions and public property," Umar said.
The official said it was "the first time" Palestinian police had confiscated weapons or ammunition since September 2000 when Palestinians launched their uprising against Israeli occupation.
"These are gangs that challenge the authority," he said. "The campaign is not going to end, it is going to move from one town to the other."
The raid on Saturday followed an escalation in recent days by armed Palestinians against deputies of Abbas, whose new government was approved by Parliament last month.
Armed Palestinians wounded a Palestinian policeman on Friday, shooting at a police station in the West Bank city of Nablus after police refused them permission to see a prisoner.
Another policeman was injured in a separate incident on Tuesday in the West Bank town of Jenin when an armed man opened fire near the Palestinian Interior Minister's motorcade complaining he had not coordinated his visit with the resistance groups.