JERUSALEM  Tensions were rising on Wednesday between Fatah and Hamas, the two main Palestinian political factions, over a leaked American diplomatic cable and ongoing accusations by each side regarding the other’s arrests, plans and statements.

Gen. Adnan Damiri, spokesman for the security services of the Fatah-dominated Palestinian Authority in the West Bank, called a news conference and said that Hamas rockets, rocket launchers and automatic weapons had been found in Ramallah and Nablus. This was evidence, he said, of plans by Hamas to attack fellow Palestinians.

“The security institutions are carefully considering the seriousness of the incitements to killing and the chaos that the illegal Hamas militias and leadership are carrying out in Gaza and Damascus,” he said, referring to the movement’s leaders, who are divided between Gaza and Damascus, Syria.

Earlier, Fatah denied the assertions of a cable from 2007 released by WikiLeaks, in which the head of the Israeli Shin Bet security service, Yuval Diskin, is quoted as saying that Fatah forces asked Israel to attack Hamas in Gaza and that the Palestinian Authority shared its intelligence with Israel.