Gunmen have killed at least four people in a raid on the Gaza home of a Fatah official, ending a third truce in as many days between Palestinian groups.
 Dozens have died since fighting flared on Friday | The dawn killings came hours after the ceasefire was agreed by feuding factions Hamas and Fatah. Earlier an Egyptian diplomat was wounded, and mortars hit the office of Palestinian leader Mahmoud Abbas. Almost 30 people have died since fierce fighting broke out in Gaza on Sunday, including 14 in one attack on Tuesday. The violence is the worst since February, when Hamas and Fatah agreed a deal to join a Palestinian national unity government. 'In cold blood' Despite the latest ceasefire deal, Wednesday morning began with a familiar spate of attacks. Grenades were thrown at a Hamas police post, reports said, followed by mortar fire targeting Mr Abbas' office. The most deadly attack then followed. Fatah said that up to 200 Hamas gunmen surrounded and attacked the home of Rashid Abu Shbak, a Fatah chief who controls three of the Palestinian security forces. Part of the house was burned down, and at least four security guards were killed although Rashid Abu Shbak was not home at the time, a Fatah official said. The official, Abdel Hakim Awad, quickly blamed Hamas for the killings. "All [Hamas] are killers from top to bottom, all are implicated," he said. "What is happening is killing in cold blood, and this is criminal." Revenge The renewed violence quickly undermined Tuesday night's attempt to broker a ceasefire, the third such truce brokered since the violence first flared at the weekend.  | HAVE YOUR SAY  You can't expect any kind of resolution to the conflict in Gaza for as long as Hamas is in power  Brad, Japan | Both previous agreements, which have been brokered with Egyptian assistance, lasted little more than a few hours. The latest accord floundered almost immediately. An Egyptian diplomat was shot in the hand, reportedly as he walked along a Gaza street to test whether gunmen were sticking to the deal. Gunfire then echoed across Gaza into the early hours of Wednesday morning. The BBC's Aleem Maqbool, in the West Bank town of Ramallah, says whatever the militants started fighting for, the killings are now in the name of revenge. Palestinian Authority President Mahmoud Abbas has urged an end to the factional fighting. Street gun battles had raged throughout Tuesday, with schools and businesses closed and most residents of Gaza City kept indoors. In the worst single attack of the unrest so far, at least 14 people died in an attack on a Fatah military training base near the Karni crossing point with Israel on Tuesday. | 
