GAZA (Reuters) - Israeli troops killed a Palestinian fighter and wounded two others close to the border fence in the Gaza Strip Tuesday, Palestinian sources said. An Israeli military spokeswoman said troops had opened fire at militants who detonated an explosive device close to the Gaza border fence with Israel. A group affiliated with the Palestinian President Mahmoud Abbas's Fatah movement said the man killed was one of its members. Medical workers identified him as Amjad al-Zaanin. Gunmen in Gaza have stepped up cross-border attacks in recent weeks, drawing Israeli strikes that killed 13 Palestinians, most of them militants, in December. Militant groups in the Gaza Strip said last week they would stop firing rockets at Israel after Egypt cautioned that any further shootings may elicit a strong Israeli response. But four rockets were fired at Israel Tuesday, the military said.