However, none of the groups claimed responsibility for the abduction of the three Israeli teenagers.
The gunmen were speaking at a joint press conference in the Gaza Strip. They included members of Hamas, Fatah and the Popular Resistance Committees.
The gunmen said that Israeli threats against Hamas and the Gaza Strip don't scare them. They also said they were prepared to confront any Israeli "aggression."
The press conference came on the fifth day of Operation Brothers's Keeper, where soldiers have launched raids in Nablus's Balata and Awarta areas. A total of 200 suspects, mainly members of Hamas, have been arrested since the start of the operation.
In addition to the arrests, soldiers on Tuesday seized guns, explosives, and grenades. A security source said a large quantity of weapons was recovered during the arrests, describing the raids as a large-scale counter-terrorism clean-up operation.